I installed a theme for Windows that replicates as closely as possible on Windows 8, the GUI appearance of Windows 95. It does this by using a High Contrast Colour scheme with Win95's colours. I tried to play Minecraft with it on but I found that it didn't work:

Setting the windows theme to one that has a High Contrast colour scheme stops the graphics from updating properly. See attached screenshots on how to recreate.

NOTES:

*The only OS I know this to happen on is Windows 8. It will probably not apply to Windows 7 or earlier because its colour scheme system is different

**The graphics will still work normally if a theme with a standard colour scheme is used until the title screen is reached and then is switched with one that has a High Contrast colour scheme.