[RESOLVED] My arcade-pc not play mng but it play mp3. Help me!

Hi.
I created a PC for use with GameEx.
I installed Windows XP and I have disabled almost all processes, only essential (15) and I installed the avi codec pack.
I work with GameEx everything right, except that it not play videos avisnaps mng, although that play sounds. Nothing appears, mng, PNG snaps... but play mp3.
Do I have to install any software to work?
Do I have to enable a Windows XP service?
Do I have to install a windows program that has been disabled?

Thanks and I hope your help.