As long as you don't need to plug into networks dells are ok. We have shitloads of problems with them at the office. I got lucky and got an off brand one (panasonic) and haven't had any problems with it and I've been using it for over a year now. It's very fast and reliable, plus it is the re-inforced model so you can drop it and it most likely will be ok. Only problem with the re-inforcing is it weighs half again as much as most laptops.
For my personal computer I am going to go with Alienware, one of my best bors got one and the thing fucking rocks. They are pretty pricey though the one I am looking at is around $2,800 and they can go in excess of 5K if you really go wild on options.
Cheers,
Scotsman