Try this to work around this issue, follow these steps:
In the Display Properties dialog box, click the Settings tab.
Click the Advanced button.
Click the Adapter tab, and then click the List all modes button.
Select the resolution, color depth, and refresh rate that you want and click OK.
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This is different that just setting the Color quality on the settings page. If you haven't been there already I suspect the "game" changed your mode and you have to change it back. Bad GAME! Beware!, check the setting other users have for this option before you change yours. If you choose the wrong mode (particularly refresh rate) you may
screw up(<-techie term

) or even damage your monitor/video adapter.
BTW, I "feel your pain" re help files but when it comes to troubleshooting it is one of the first places I look. On XP the help and support is much more robust, especially the search of the Knowledge Base part. By doing a serch in Help I may not find the answer right there but it gives me key words to search on when I go searching the Knowledge base at MS or even at Google.
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"Experience is a hard teacher because she gives the test first, the lesson afterwards."