i conected my 37 HD TV that supports 480p,720p,1080i to my computer through a DVI to HDMI cable but i cant see the edeges of the screen and i dont see any options in the TV to make the screen smaller and i also try putting it in a diferent resolution but it still doesnt work. is there anything i can do to fix this?

Thats the effect of overscan, typical TVs have up to 5% cutoff all around the edges. Some sets can adjust that in a special service mode, but many sets can't adjust it at all unfortunately.
I'm looking carefully at models for a new HDTV and I want to ensure the model I get has very little overscan and has adjustability if possible. I'm looking at the new Panasonic model 1080p plasmas coming out that have a menu setting to enable zero overscan for full HD image displayed!