Need help picking a Monarch Computer

[TheMetetron]

I think I want to get a desktop from these guys, but they have so many weird options and I'm not THAT computer saavy that I don't want to mess something up. What I want:

- At least 250GB HD. I would take a bigger one if it was cost-efficient. I also have a 250GB External already, so I think I'm good.

- At least 1GB of RAM. 2GB would probably be preferred, though I'm not sure if getting it on here is best. Also, what the hell is DDR2? Made me seem like getting all the RAM there was better, but I'm confused.

- P4 3.0-3.2 Ghz Processor. Is that enough? I remember reading that processor speed isn't really all that important.

- DVD +- RW 16x Dual Layer. A separate DVD-ROM wouldn't be a bad idea either. I think cheapest one is the idea here, no?

- Video card. I want to be able to use 3 monitors. I think this means I need 2 video cards. I also want a TV-tuner to be able to watch/record cable on one of my monitors.

- I obviously need Windows XP. Home is fine, but is the Media Center upgrade worth it? I have no knowledge of it myself.

I think that's all... if someone can help me pick out the right components, I'd be super grateful. Also, if Monarch isn't the best place for this, someone let me know.