What is the best Hardware Decoder?
Most standard display cards today come with a TV-Out option which gives a better image quality and allows for a greater degree of control. Hardware decoders are just not needed these days.
A Hardware Decoder card is of great use if you plan watching DVD movies on a TV and would rather use the computer to do it cheaply (with an older machine).
Using a hardware decoder on a PC Monitor is usually a bad call as most of them use a pass-through cable which degrades the monitor image quality. The reason? the cables are cheaply designed, just compare the cable you get with say a Hollywood+ decoder to a cable that comes with the Diamond Monster II, it's practically half the width.
This is most evident on the Creative DXR2 where the monitor quality is awful. As a rule, it is advised to use a Software Decoder if you plan to view movies on your monitor, with the exception of very slow computers (under 300-350mhz).
When picking out a Hardware Decoder there are certain things you may want to consider: support for unlimited Multi-Region and possibly support for MacroVision stripping, and of course you must not forget the image quality.
The monitor image quality can truly suck on some of these cards, but the TV quality is usually pretty ok.
MacroVision stripping and Multi-Region support is pretty rare among the decoder cards. I am currently aware of only two cards that have these.
Recommended Hardware Decoder cards:
The 3DFusion Diva card, while not MacroVision stripping,
is rumored to have the best TV image (though the image quality on both other cards is very good as well).