i need a new one, my dell is falling apart. it's been 4 years. by default, we've gone with dell for years.
the only hard and fast requirements are the biggest/highest-res screen possible. dell has a 17.3" Full HD option. i wish screens had advanced more, as my current one is a 17" with higher resolution 1920x1200.
aside from that, at least 4GB RAM (obviously), more if there's a tangible benefit.
There is more of a benefit now because the OS can recognize more than 3GB. WinXP had a 3GB limit so it wouldn't recognize more than 3GB. Vista addressed that but Vista is the ME compared to Win7.