|Hey, I found out the solution to this problem, at least for me.|
I'm playing starcraft on an HDTV myself have an HDTV hookup and the image always displayed as tiny, and I knew because of having an analog display before to the tv that it was possible to have a much higher stretched resolution.
I screwed around with my graphics options in the ATI catalyst(I have an hd4650) and clicked "Enable GPU scaling" in attributes.
I tried starcraft and it worked perfectly. Didn't have to have any target path options or anything. There is a small wall of an inch or two of black that the image doesn't scale to but that's because there isn't an option for overscanning while in GPU mode so it uses the default scan.
Hope this helps somehow. I'm sure there's a similar option with nvidia cards if you are using one.