I already have a free flight lined up to San Diego for New Year's. I will be rollerblading in the sun while the rest of my friends are freezing in New York. The second point of interest is the reimbursement payment itself, usually given at the end of the semester when you get your grades. A lot of companies withhold taxes on this like you were receiving a bonus. This is not necessary for them to do in certain situations.
Some companies have a general tax withholding policy.
See if you can exempt yourself from it if you qualify. Following payment you can register for classes. Of course, this being your first semester, you have core classes to take and the options are few. It's all about personal preference here, but the one thing I can tell you is that after working a full day then going to class, most will have a hard time doing homework that night. Stern has a Web site where students' evaluations of professors are listed so you can have some idea on who you want to teach you, but you can't access it until all of your paperwork is processed.