Yes, regular desktop would work. Something with some decent processor and some ram. Also, if you were building your own. I would advise you to get a low wattage power supply since it will be constantly on.
Just browsing the internetz on your tv?
I have a crappy 2003 laptop hooked up to mine and thats what i use for "media" like netflix and watching streaming tv shows, the pronz!!!, internet browsing, homework, I just added a wireless mouse and keyboard to the whole setup. It works fine. Slow, but works. I like laptop cause it's small and can be hidden easier than desktop.
But if you have some money to spend, get a laptop/desktop with hdmi if your hooking it straight to your tv.
Threaded Mode