OK, I've been saving for a few months and have some money to spend on myself. I'm purchasing a laptop, but I would like some input from you guys (and girls

) before making a final decision.
I need a computer to last me through at least four years of college. On top of that, I'm going for a computer science bachelor's, so I'm doing more than just word processing (which my current 366 MHz computer can handle

). My absolute top budget is $1700, but I would like to keep it around $1400.
I have been looking forward to a Compaq Presario 1700 laptop: PIII 1.2GHz, 256 MB SDRAM (max 1024), 30 GB HD, modular floppy & DVD/CDRW drives in a 5.4 lb case with Win2000. (There were some other goodies too, like S-Video and stuff

) Until recently, it was only $1374.
Recently my dad recommended I look at the P4 or Athlon-4 models, as these will likely not become outdated as quickly as the PIII's are. The best I've found is the Compaq Presario 700 series - similar configuration as above mentioned model, but with P4 processor and DDR SDRAM instead, Win XP Pro, and it's a three-spindle device (HDD, floppy, and DVD/CDRW all in the unit). I've also found the Toshiba Satellite 2400-S202: P4 1.6 GHz, 256 MB DDR SDRAM, 30 GB HD, DVD/CDRW, floppy, and WinXP Home in a 7.5 lb case for appx $1650.
I need a laptop because there is a likelihood that I will be commuting to college (it's only 10 minutes up the road). I've already ruled out a desktop because of this. Also because of this, weight and size is a slight issue (nothing more than 8 lbs). Ethernet is a must, and I need nothing more than a 14.1" screen, but don't want anything less.
Do you have any other suggestions, or am I on the right track with these particular models?
One other problem: WinXP Home Edition doesn't work on my (future) college campus' network. I have to have either XP Pro or Win2k. XP Pro is available free legally from my college; would it be more easier to get a laptop with XP Home and then upgrade, or just pay the extra $50 for the right OS shipped with the machine?