By FAR the best software to display closed captioning (as opposed to subtitles) is The KMPlayer (free, note there is also a KMplayer for Linux. That's different software, this is for Windows). I've been looking into this for a while as my father is very hard of hearing.
To get CC just hit F2 to open the preferences menu and on the left go to subtitle processing -> multi-sub/etc
And then on the right the menu that brings up there will be a tab at the top that says "advanced" click that and then there will be a drop down box that says "Decode CC" choose "As Text." That should work, you will also have complete control over the appearance of the closed captioning.
You can change the color, font, outlining, size, opacity, shadows, and so on and so forth (look in the font style section of that menu).
When installing just choose the default settings. There is also a wizard to choose settings for the program, just use what you want there. To open a DVD currently in the drive hit Ctrl+D. Hit 2 to get the window to normal size. There are also tons more options for customization.
If you enable/disable closed captioning while playing the DVD, you'll need to hit stop and reopen the DVD to get the new settings. However, it should play the DVD from where you left off.
Download Link
Example I just did to show just how much you can customize the look of the closed captioning (I wouldn't recommend these settings!)
and another:
If you have any questions or problems just ask.