WTF... I have tried to reply to your post FOUR **** TIMES NOW, and EVERY TIME, it says I am not logged in... This is REALLY starting to **** me off.......
I would recommend staying with the Socket 478 setup you have. Upgrade the Mobo to DDR2 if you want, go with 1 Gig of RAM, and get a DVD Burner.
The system requirements for Tron 2.0 are NO WHERE NEAR enough to have to consider getting a PCI-e video card.
What are your current system specs??