I've got an ancient Dell Optiplex GX1 500L+ that'd I'd like to upgrade completely. Before I continue I want you to know I'm doing this for fun so please don't say you'd be better off buying a whole new computer. That being said, here's what I wanna do:

I've already upgraded the hard drive, sound card, and got a new cd/dvd burner. Here's whats left:

1. New motherboard
2. More RAM
3. New graphics card
4. Faster CPU
5. Sexy monitor
6. Nice looking case to put it all in!

Here's the thing. I dont know exactly what brand and all that that I want for all this stuff. I'm going to buy it one at a time, by price (lowest to highest), starting January of '07. So why am I here? Well as I said before I dont know what I want for sure and I'd like you to stop me if I make a wrong turn. Another thing is this. Lets say I get a brand new motherboard and tower case. How do I know if everything will fit the way its supposed to?? I also know that there are different types of RAM that may not be compatible with some types of motherboards (same goes for CPUs I think right??). So, how do I obtain all of this information? I'm planning on buying all of this from newegg.com by the way. Thanks in advance for any help!