Depends on what you are doing with your computer. For gaming, you want the better mid/high end graphics like nVidia GTX or the ATI 2xxx lines of chips. For regular home use or office use, any integrated graphics in the last 1-2 years are good enough.
For laptop, make sure you buy something with a mobile processor instead of the desktop ones. Desktop processors can easily overheat and shorten its life compare to the mobile ones.
At least 2GB of ram, desktop or laptop. 4GB would be ideal for today's price. Only SATA drives are used now, PATA/IDE are antiques for aftermarket only. Try to get one with DVD R drive, or upgrade it after you bought the machine, they are only $20-30.
To me Intel/AMD are about the same, both good enough for the price. If you are into overclocking Intel's wolfdale (Pentium E, with 2MB cache, I think) chip is very good overclockers.
In terms of build quality, you get what you pay for and most OEM components are low/acceptable quality compare to the high end components you get from name brands in components market.