I've been meaning to get my tutorial back up on this, but I just haven't had much time.
1) Uninstall from the Add/Remove Programs menu, if possible.
2) Reboot
3) Delete the entire MOH directory manually (Usually C:\Program Files\EA Games\Allied Assault\) If there's nothing else in the EA Games folder, delete that as well.
4) goto
http://www.jv16.org and download the RegCleaner
5) Run the regcleaner, and choose Tools>Registry Clean>Do Them All
6) Once it has deleted any bad keys (or, after its done, you delete them), reboot
7) Reinstall MOH (DO NOT BOOT THE GAME BACK UP UNTIL THE FINAL STEPS)
8) Install the V1.11 patch.
9) Run the config.exe file in the MOH directory
10) Run the game.