Selling/Building a PC.. Advice?

Lately I've been playing with the idea of selling my system to build a new one.  What do you guys think, would this be worthwhile? 

-WinXP Pro 32 - SP2

-AMD64 3000+

-2GB RAM (2x 1GB, 2 slots total)

-NVIDIA GeForce 6800 (vanilla)

-DVD-R (8x), CD-RW (52x), Floppy Drives

-420w power supply

-6x USB, 2x Firewire, the rest is pretty standard.

-/Doesn't support PCI Express/  

So tell me, would it be worth it to try and sell this to make a new system?  I want to use it for, well, video editing, graphic design, and of course, games.  There's a number of things I want to upgrade, and I feel if I kept this system and just upgraded what I want, I'd have near enough to build a system with my old parts. 

So basically, will I be taking a loss?  How much could I get, and what am I looking to spend in a (hopefuly) middle-top tier media editing/gaming comp? I can look up anything else, if you need.

Also a 20" CRT.. it's hueg.  I'd part with my speaker setup, it's just two desk top speakers and a sub.  I could toss in a webcam and mic for kicks. :P

honestly i would only sell off certain parts, mostly the mobo and CPU. unless you really want to upgrade to faster RAM seeling off then re-buying RAM seems foolish. Your video card is still running most games very well. Besides the mobo and cpu i'd sell the case and PSU. You prolyl coulndt give the floppy drives away, and you could prolly re-use the others in your new computer.

Hmm.. Mobo?  I suppose that'd be a good way to go about it.  2GB of RAM should get me by for a while, eventually I'd like 4-8. 

What do you think I could get for each of those pieces?  Considering they're used.