Apple Powerbook 17", hands down. In a class of its own.
AVOID Dell at all costs. Repeat, AVOID Dell at all costs. I regret buying my Dell. I even bought the three-year service plan. I have never had a pleasant customer service experience with them. Terrible, terrible company and NO customer service. Good luck getting someone on the phone who speaks English.
The next computer I buy will definitely be an Apple. A bit more expensive but worth the cost. Especially if you want to be doing graphics stuff.
Check it out:
www.apple.com