WMP 12 lags when opening a movie file

I have windows 7 64bit, everytime i launch a movie file like an AVI WMP 12 doesnt function when the movie is playing. I can not move the slider bar over nor close the player until like a min later it starts functioning again. when i use VLC player it works fine no issues. I know that some movies that i download are AVI files but require other codecs to be installed to use with WMP. the only codec i have installed for WMP 12 is the AC3 filter which is required for HD movies. which codec pack should i use for Audio and video collaboration. I think this is why the player lags so much.

and when i say download movies this is from Android market that i buy. Windows media player on Windwos 7. the actual player it self doesnt function for a like 30 seconds while the movie is playing. the outside skin is not functional nor the X to close it not sure why it does this. i unchecked program compatiblity with my Nvidia drivers so not sure what else would cause this very annoying.

any insight into this. I have read other people had this same issue with WMP 12 on Windows 7. whats the deal.