Oh, some general thoughts on laptops:
I'm a big, big fan of widescreen notebooks.
15.4" screens are too big to carry around all the time. 14.1" screens are *just* the right compromise between usability and portability. 13.3" is also great if the resolution is over 1280x720, especially if you want a notebook on the smaller and lighter side. Every pound counts when you're carrying it around a lot.
Get at least 1GB of RAM (RAM is cheap to add after purchase, but you don't want to use it much with less than 1GB), and get a Core 2 Duo processor. No AMD processors, no Pentium processors.