
No.  No.  NOOO!!!

The ground (green) wire is for safety.  No current is supposed to flow in it
under normal conditions.  This means that there's normally no voltage drop in
it either.  It is supposed to be safe to touch the ground wire... even if
you're grounded in some other way at the same time.  

The neutral (white) wire is, as Dave Vanderbyl correctly said, the return for
the hot wire.  Since current flows in it, there's a voltage drop.  If you
plug a heavy load into a properly-wired grounded outlet, you can commonly 
measure a volt or so of difference between neutral and ground.  

They are supposed to be connected together at the breaker panel... but nowhere,
repeat NOwhere, else.  (Well, almost.  There are strange exceptions for things
like sub-panels.)

What you CAN do if you want three-prong outlets without additional wiring is 
to use a GFCI outlet (or breaker, but the outlet will be cheaper).  In fact,
depending on where you are putting your new outlet(s), a GFCI may be *required*.

There is a FAQ on electrical wiring, posted regularly to rec.woodworking and
news.answers.  It goes into great detail on these issues (including GFCIs) and
you should probably read it before asking any more questions.  I'll mail a copy
to you, append a copy here, and will ask the writers to cross-post it here in
the future. 