one thing to consider acadia is my first computer i built i had the company that i bought parts from, i had them install windows on the hard drive for me and install the chip to the mobo, thats all. and yes, you want the disk...no start up crap. that was the only part i wasn't sure about (for myself) and they happily did it for me. other than that you plug crap into the little plugs, they usually only go one way (so you somewhat safe there ;P). the mobo come with a handy guide that shows you where your agp slots are, this goes here that goes there. i bought from 3 different places. 
zipzoom and fly, newegg and can't remember the company that builds/installs/sells stuff that did the initial harddrive and chip install. i think i just googled and typed in "build your computer for you" and waded through the mess.
just be careful and go slow. your not building a rocketship. mine started right up first time and i've been sailing ever since.

of course that doesn't cover the unexpected hard drive crashes or xp locking up for no reason. you can thank mr. gates for all of that crap.

you got a lot of good info from the earlier thread, some good peps had some good stuff for you to buy. we all love buying with your money.

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