I haven't trusted Tomshardware for years. He gets paid under the table from manufacurers and as a result, is hardware reviews have always been slanted and biased and the forum isn't much better. Anandtech, overclock.net or hardocp.com are better choices.

If you can swing the cost, go with an quad core as that will greatly extend the life of your PC usage down the road as everything is becoming multi core based. Do no less then 4 gigs of RAM, 6 is even better and HDD's are so cheap nowadays you can get a 600gig- 1 terabyte drive for screaming low deals in most machines. Onboard video is fine if you don't plan on gaming. Decent 5.1 onboard sound is fine as well for your use.

FYI, your old machine is running an older Pentium 4 which was top of the line back in 2003-2004. Needless to say, it wouldn't hold a candle to todays current dual and quad cores, either AMD or Intel. Download and run CPU ID and it will tell you everything about your hardware specs, and then some

http://www.cpuid.com/cpuz.php

You can get a nice specced machine for less built on an AMD quad core, but Intels quads will still beat it in most areas, they just cost a bit more. I"m also from the "build your own" camp, but for alot of tech challenged people, its simply not the best option. I build gaming rigs like this for myself as gaming and PC's are my primary hobby as well as career.