I'd need to know which one you refer to as there are many different types there.

Most are incorrectly described, as most are leads, which are NOT converters. As for the "box of tricks" converters - for that price I wouldn't expect much, if anything, from them.

A TV's interlaced signal is far different to that of a PC's RGB signal. For a start, whilst a video picture may be transmitted in RGB, the sync is only on green, whilst a PC has no green sync, instead it has a two stage sync - vertical sync and horizontal sync. Likewise, most PC's output video in progressive format, and TV (CRT) only accept interlaced (very few CRT TV's accept a progressive picture.

However, if your TV is of the plasma or LCD variety, you may well be in luck, as normall with these, the only thing that is needed is a transport lead. An LCD TV is basically a larger version of a PC monitor anyway, and many have (S)VGA inputs (the blue, analogue RGB input found on the back of 99% of PC's), so a simple (S)VGA lead from your PC to an LCD or plasma TV is all that is needed to display your desktop on your TV.