I'm a Mac man myself. Even PC World Magazine rated Mac as the most reliable computer with the best customer service. I bought a Power Book about 9 months ago and have been thrilled. I was a PC guy before that but just got sick of all the Windows problems. I went to Mac because I thought, "It can't get worse."
I have had no problems with compatibility problems or anything. In fact, I can run Windows XP on my Mac if I have to.
My money is on the Mac.
If you don't want the a Mac, here is my suggestions:
1. DO NOT get a Gateway, the quality has gone to hell and the customer service is crap
2. HP/Compaq- got price, but can be very touchy
3. Dell- more reliable then most and has better customer service than the others.
If I were looking at a PC laptop, I would probably go Dell. I do suggest grabing a Laptop Magazine and looking at there ratings.
My IBM Thinkpad died in Sept. and it was only 3 years old. I had a problem last year that IBM "fixed" while it was still on warranty and then 2 months after the warranty expired I had the problem again. Apparently there are 3 parts to the monitor that should have been replaced and only 1 was. To fix it would have been $600 or so.
I know that if you're in optometry school at PCO, ALL OF THEIR CLASS NOTES are online so, it would behoove you to get a laptop...as its easy access (but again, only if you live in Penn.)
as far as computers go, i have the Sony laptop (its not really mine, i share it with family) but it doesnt have all the extras like CD burners etc. you can just do email and type papers on it basically
and sinceyou'll be in opt. school, thats all you'll need really.
Theres lots to choose from, i basically agree with what rpames said. Even though a lot of people flame the VAIO lineup, i still think they're great (the compromise is between the size/weight to the types of features). Try to stick with Intel Centrino M processors (extended batterly life).
If you can afford it, I guess try to get a really good one now so your not beating yourself later because your unit is obsolete.
I would choose between the VAIO Z1, or V505 series. My other choice would also be an Apple PowerBook G4