VLC Media Player is probably the best media player for Windows, specially for videos. It plays almost all the media files I throw at it. But our android-verse is yet to have this. Though, Austen, a software developer has compiled his own build of VLC for android.
It has a very neat interface with all the basic functions one would want from a media player. Switching between videos and music is easy with a touch. It played well most of the videos that I tried on it and songs as well. (Download links inside the post)