If all you're planning on using it for is watching movies I would suggest:
Celeron D 3.06GHz
You shouldn't need anything more powerful than that. And while it does use the NetBurst Architecture it's the newer 65nm manufacturing process so it'll run cooler than older Celerons.
Crucial 1GB DDR 400
Yes, you might get better memory performance with a 2x512MB setup but you only have two memory slots and that would make upgrading later more expensive. Everyone has their own preferences for memory but I've never had a problem with Crucial.
EVGA GeForce 7600GT 256MB
Middle of the road card that should handle movies and more if you ever decide to do anything more, the price is good for the performance.
I would also recommend these:
ZALMAN ZM-RHS1 VGA RAM Heatsink
The 7600GT I listed doesn't have heatspreaders on the actual RAM and these do help keep it cool (they will make an even bigger impact if you don't OC the card, which you shouldn't need to).
I wasn't sure of your budget so I picked components that should meet/exceed anything you'll need for what you said you wanted to use the rig for. PM me or reply here (I'll subscribe to this topic) if you have any more questions or want to get the costs down a little more (also if you've budgeted more for this let me know as there are a couple of things that could be changed to give you a better system overall).
Hope I've helped,
-David-
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