I'm a nUb when it comes to PC hardwhere also, but my dream PC would be along the lines of...
4 GB RAM, 300 GB Harddrive, Beastly graphic and souns cards, One of those fancy CD/DVD in one burners, Audio/Video, and Cable hookups, and plenty of USB ports. Water cooled interior, Oh and can't forget a 21 inch monitor and nice speakers

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Kind of a combination of a gaming, and media PC.