There are some that get the demo and then try some addins to make it fully functional. Please tell a bit more 'story'.
Bob
Memories on TV now wants to sell me a MPEG2 plug-in to make my "free" upgrade functional. However, there seems to be a myriad of free plug-ins available on the net.
Is there some reason that I can't use one of the free ones, and if so, which one?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic