hooking up t.v. to p.c. via dvi

I just recently got a new p.c. with a dvi output on it. I thought I was in luck cause my 56" rear projection rca had a dvi input.I went ahead and got a dvi cord and hooked the two together. Hoping to watch movies and what not that I have on my p.c on the tv.

Well I can get a picture on the tv but it is just the background from my desktop. no icons or anything, When I ran a movie on the p.c. in full screen, or even on small screen, the picture on the t.v. stayed the same with the back ground.

is there anyway to use my t.v. to watch movies without setting it up as primary monitor.

Any help or suggestions would be greatly appreciated

 

nevermind I'm an idiot .....

 

I also want to do the same thing but I have to buy the video card first---would a 64mg card be good enough to play avi from pc to lcd tv???