I have spent way too many hours over the last 3 months pricing laptop computers... both in terms of quality, which can cause expense later, and outright cost of the system. Anyway, this is what I have found:
Compaq: Good quality machine for very few bucks-I am writing on my girlfriends presario 2500 now ($1200)-but it sucks hard for graphics and games. This is just a simple work machine. The same goes for all other compaq models I checked out.
Dell: You can get a great deal on an inspiron 8200 with a warranty on ebay, but they don't make them anymore. They replaced it with the 8500, which I have seen, and would never buy. The screen is 15.4 inches in the diagonal dimesion, but only 8 inches tall! This is an inch shorter than the average 15 inch laptop. It is really a DVD machine.
IBM: I have used IBM laptops at work, and know many avid IBM fans. They are great machines, but cost way way way more than I would ever want to spend. $2000 won't get you much when compared with the Sager 56XX series.
Toshiba: I wasn't impressed with the one I have used in the lab, but I can't say that goes for all I have seen.
HP: Really the same as Compaq. The two companies have merged, and both have poor graphics capabilities as I understand them.
SAGER: I am going to buy one in the next couple of months. They are hands down the best bang for buck available. I would suggest telling her dad to spend a few minutes looking over the sagerforum, and possibly talking with someone at PCtorque. Get a Sager in my opinnion.