If you own it, I'd say use it. However, I would do things in this order...
First off, make sure to uninstall any other "codec packs" or standalone codecs that you have other than CCCP. Also, uninstall ANY other DVD Playback software you might have installed, including Nero Showtime or anything similar. It is always best to have just ONE DVD playback engine installed at a time.
Next, install PowerDVD and get it licensed. If it "offers" to take over your file associations, politely de-select EVERYTHING. (Sometimes you need to choose "custom" or "advanced" when going through the installer in order to make these choices.)
Next, make sure to update PowerDVD to the latest version. You can download updates here:
http://www.cyberlink.com/multi/download/updates_112_ENU.htmlOpen it up and make sure it works.
Lastly, reset CCCP. This will ensure that your filter setup is still correct. You can do this by going to
Start --> All Programs --> Combined Community Codec Pack --> Settings. Then, in the dialog that appears, click Next. In the next page, check BOTH of the boxes at the bottom under
Special Settings (Reset all settings and Re-register filters). Then click Apply.
You should be all set then. MC will probably find and use the Cyberlink decoders all on it's own after this.
If you want to add some additional functionality (Real Media support or Quicktime Alternative for example), check the DirectShow Playback Guide for further details and tips. You can also install XviD if you want to use it to encode (create) video files, but make sure to uncheck the option to use XviD to playback supported media types when running through the installer. If you won't be making any video files of your own, then don't bother. You can always install it later if/when you decide to make some, and you'll always want the newest version anyhow...