Ok, as the subject states, when my brother double clicks the Morrowind shortcut on the desktop the window opens like for 3 seconds, then closes...and the game doesn't run

What's odd is the game was running fine this morning, they got home from school and it wont run.

I dont know much about this game I'm just the "trouble-shooter" of the household.....lol.

First do a reboot, or a shutdown, let it sit for a minute and boot. Check and see if it works. Do a virusscan and a spybot scan to see if the system got infected. If you have an always on internet connection, it can happen at anytime. after a reboot, open the system settings under control panel and see if any yellow exclamation points show up, and also during boot, watch for a memory count. You might have had a chip go bad, or some other part. You might open the case and see if it has gotten full of dust, if so, blow it out with canned air. While open, check and make sure the memory chips are fully seated, as well as the video card and any other add-on cards. Run the computer with the case off, and make sure all the fans are working, and after running for awhile, see if the game will run. Might be an overheating problem if it does run. It is most likely something along those lines, assuming nothing was installed or configuration changed while you were gone.

if none of that works try uninstalling the game then installing it again. If a file was corrupted it would then be an original file then.