MPC is standalone meaning it isn't installed. It is also the best media player available for free, so you might just want to keep it. It won't interfere with anything else you have on your computer.

Also when it comes to codec packs, there are many to choose from. It is extremely important to NOT install more than a single codec pack.

I have had very good results using the Combined Community Codec Pack Combined Community Codec Pack

But again I can't stress enough that if you want to install it, make sure to uninstall all other codec for video.

note: If you use vobsub, CCCP is not recommended as these don't work well together.

note2: MPC and ZoomPlayer are included in CCCP installation, you can choose to install them or not. I usually don't install ZoomPlayer as MPC covers everything anyway in my opinion.