Have you taken a look at the reviews here on Cnet? I believe they are both fairly customizable so either one should be able to suit your needs, especially since you don't think you will do any heavy gaming or running large programs.
Windows Outreach Team
Is the HP Pavilion a6710t desktop PC a good computer to purchase to use for basic computing? For email, web surfing, and word processing? How would it stack up against Dell's Vostro 220 MT? About the same? Better or not as good?