Well, see, if you want an answer, you need to provide the necessary information. If you consider it vital information that you are using a desktop machine instead of a laptop, you need to say that. (I don't consider that vital information in this case.)
The iMacs have a mini-DVI port on the back, so you'll need a mini-DVI to HDMI adapter or mini-DVI to S-video adapter. (The HDMI would be better.) If you're using a desktop other than the iMac listed at the bottom of your messages, just look up its specifications to determine whether you need DVI or mini-DVI. Then follow the directions
here for how to make it go full screen, etc.
I don't know anything about the reviews you mention, so if you want more information about why these adapters wouldn't work well on desktops with Intel chips (which sounds fishy to me), you'd need to tell us where to find them.