<PAGE>
 
                                                                     EXHIBIT 2.3
                                                                                

                                   AGREEMENT
                                   ---------

     AGREEMENT, dated as of January 25, 1999, by and among United Internet
Technologies, Inc. (formerly known as United Leisure Interactive, Inc.)
("Seller"), Netcruise Interactive, Inc. ("Purchaser" or "Netcruise"), Genisys
Reservation Systems, Inc. ("Genisys") and United Leisure Corporation ("ULC").

                              W I T N E S S E T H:
                              --------------------

     WHEREAS, the parties hereto are parties to that certain Asset Purchase
Agreement dated as of June 30, 1998 (the "Asset Purchase Agreement"), pursuant
to which Seller sold to Purchaser, and Purchaser purchased from Seller, all of
Seller's right, title and interest in and to (i) the License, and (ii) the
assets owned by Seller and described in Exhibit B attached to the Asset Purchase
Agreement (collectively, the "Transaction"); and

     WHEREAS, the parties hereto are parties to that certain Agreement dated as
of October 28, 1998 (the "Amendment Agreement"), the purpose of which is to
amend certain provisions of the Asset Purchase Agreement and to provide for such
other matters as therein provided; and

     WHEREAS, the parties desire to modify and amend further certain provisions
of the Asset Purchase Agreement and the Amendment Agreement;

     NOW, THEREFORE, the parties hereto hereby agree as follows:

     1.   All capitalized terms not defined herein shall have the meaning
ascribed to them in the Asset Purchase Agreement or the Amendment Agreement, as
the case may be.

     2.   Paragraph 4 of the Amendment Agreement, entitled "Shareholders
Meeting", is hereby amended by deleting the third full paragraph thereof in its
entirety.  For purposes of clarification only, said deleted paragraph is set
forth below:

     "If, for any reason whatsoever, the aforesaid 1,100,000 Shares and the
     Warrants are not issued to Netcruise on or before June 30, 1999, then, in
     addition to any and all other rights and remedies available to United, at
     United's option, up to four (4) members of the Board of Directors of
     Genisys ("Board"), which members shall be selected buy United, shall
     forthwith resign and, concurrently therewith, all of the remaining members
     of the Board shall elect those persons chosen by United to replace them. By
     their signatures below, those shareholders of Genisys who are also members
     of the Board agree to take such action as to carry out the terms of this
     provision."

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     3.   Notwithstanding anything else contained in the Asset Purchase
Agreement or the Amendment Agreement to the contrary, in the event that the
shareholders of Genisys (not including Seller who shall not vote on the matter)
do not approve, at a Meeting of Shareholders properly noticed and duly called
and at which such shareholders' votes have been solicited pursuant to a Proxy
Statement under the Proxy Rules adopted by the Securities and Exchange
Commission, both (i) the acquisition of the Assets and (ii) the issuance to
Seller of the 1,100,000 shares of Genisys Common Stock which were not subject to
the Return and the Warrants, such negative vote shall be deemed a "Shareholder
Termination."

     4.   In the event of a Shareholder Termination, the Transaction shall be
Unwound.  For purposes of this Agreement, the term "Unwound" or "Unwinding"
shall mean one or more acts, transactions or closings, to be accomplished as
soon as reasonably practicable following a Shareholder Termination, the
cumulative effect of which is that all of the following shall occur:

     a.   All of the Assets shall be returned by Purchaser to Seller;

     b.   Seller shall return to Genisys a stock certificate representing the
Retained Shares;

     c.   Seller shall return to Genisys a stock certificate representing the
United Preferred Shares;

     d.   Brian Shuster shall return the warrants issued to him by Genisys
pursuant to Paragraph 5 of the Asset Purchase Agreement;

     e.   Harry Shuster shall resign as a director of Genisys and Chairman of
Netcruise and from all other offices he holds with either Genisys or Netcruise;

     f.   Brian Shuster shall resign as a director of Genisys and President of
Netcruise, and from all other offices he holds with either Genisys or Netcruise;

     g.   Brian Shuster's consulting fee of $5,000 per month shall be prorated
to the date of his resignation as President of Netcruise and shall cease as of
such date;

     h.   the services of Robert Eady shall cease to be provided to Purchaser
and Genisys;

     i.     Subject to obtaining the required consent of the Landlord (as
defined below), Purchaser shall assign to Seller that certain Commercial Lease
dated March 1, 1996 between Seller and 1990 Westwood Blvd., Inc. (the
"Landlord"), pertaining to the office premises at 1990 Westwood Boulevard, Los
Angeles, California;

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     j.   Genisys and Purchaser will return to ULC and Seller all documents
(including all copies thereof), including without limitation "due diligence"
material and all other confidential material, previously delivered by ULC or
Seller to Genisys or Purchaser;

     k.   ULC and Seller will return to Genisys and Purchaser all documents
(including all copies thereof), including without limitation "due diligence"
material and all other confidential material, previously delivered by Genisys or
Purchaser to ULC or Seller; and

     l.   The noncompetition clause contained in Paragraph 9 of the Asset
Purchase Agreement shall be null and void.

In the event of a Shareholder Termination, the parties agree to cooperate fully
with each other, including without limitation executing all such certificates,
instruments and other documents, and giving all such consents, as may be
necessary or reasonably requested to effect the Unwinding. The cost of the
Unwinding (including, without limitation, attorneys' fees and expenses), shall
be borne by Genisys pursuant to Paragraph 5 of the Amendment Agreement.

     5.   In the event of a Shareholder Termination and following the Unwinding
of the Transaction, Genisys shall have an option (the "Option") until September
30, 1999 (the "Termination Date") to again seek and obtain approval of the
Transaction by Genisys' shareholders on the same terms and conditions as
originally agreed to pursuant to the Asset Purchase Agreement, as amended by the
Amendment Agreement and this Agreement.  Such shareholder approval shall be
obtained in accordance with all requirements of the Securities and Exchange
Commission (the "Commission") and The Nasdaq Stock Market, Inc. ("Nasdaq").
Genisys shall indicate its desire to exercise the Option pursuant to this
Paragraph 5 by providing written notice to Seller and ULC within ten business
days following the completion of the Unwinding of the Transaction.  In the event
that Genisys exercises the Option, the parties agree to cooperate fully with
each other, including without limitation executing all such certificates,
instruments and other documents, and giving all such consents, as may be
necessary or reasonably requested to effect the Transaction pursuant to the
Option.  However, notwithstanding anything contained in the Asset Purchase
Agreement, the Amendment Agreement or herein to the contrary, the Transaction
shall not close pursuant the Option until and unless the Genisys shareholders
lawfully approve the Transaction on or before the Termination Date in compliance
with all requirements of the Commission and Nasdaq.  The cost of consummating
the Transaction pursuant to the Option under this Paragraph 5 (including,
without limitation, attorneys' fees and expenses), shall be borne by Genisys
pursuant to Paragraph 5 of the Amendment Agreement.

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     6.   Exhibit E to the Asset Purchase Agreement is hereby amended in its
entirety to read as follows:

     "The undersigned agrees to execute an agreement restricting the sale of the
     securities issued by the Company acquired in this transaction. Such
     restriction shall be for a period of 24 months from the date of this
     agreement, June 30, 1998."

     7.   All other provisions of the Asset Purchase Agreement and the Amendment
Agreement not inconsistent with the provisions hereof shall remain in full force
and effect.


     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date above first written.


UNITED LEISURE CORPORATION          UNITED INTERNET TECHNOLOGIES,
                                    INC. (formerly known as United
                                    Leisure Interactive, Inc.)
 

By  /s/ Harry Shuster               By  /s/ Harry Shuster
   ----------------------------        ---------------------------
     Harry Shuster                       Harry Shuster
Title: Chairman and Chief           Title: Chairman and Chief
   Executive Officer                      Executive Officer


GENISYS RESERVATION SYSTEMS, INC.   NETCRUISE INTERACTIVE, INC.


By  /s/ Lawrence E. Burk            By  /s/ Lawrence E. Burk
   ----------------------------        ---------------------------
     Lawrence E. Burk                    Lawrence E. Burk
Title: Chairman and Chief           Title: Chairman and Chief
   Executive Officer                      Executive Officer



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