So I have this crappy computer...its a dell 4500(5 years old), its 2 ghz pentium, only has 256 mb ram, and it takes forever to even open itunes with nothing else running. So obviously, I need a new computer. I am running low on cash, so i'm going buy a barebone kit and put what i can from this computer in to the new one. and replace whatever i cant put in the new one.

Well, I was reading through this and Ive figured out that pentium core 2 duo is faster than pentium D(regardless of what speeds say).
So which would be better for me? I'm not into gaming on the computer...I have plenty of game systems for that. I just would like to be able to having multiple things running, say, yahoo messenger(while chatting), itunes, and a couple firefox windows open, without my computer needing time to comprehend what i just told it to do... so do I really need to get core 2 duo or is pentium D good enough?

pentium D will be fine, although I'd go for the d945, or if you dont mind overclocking the d805 or the d915 either is fine.
Obviously the core 2duo is better, but if your not doing any seriously intensive, computing IE rendering re-encoding stuff you wont see the differnce between the two.
Enfact in windows XP unless playing games, you have to realy go out your way to get CPU utilisation to 100% with just an athlon 3500+