Used to be with WMP, but now I use GOM Player (haven't installed a codec once) for all videos - it's practically a better VLC player. I use it for snapshots, burst capture, animated GIF, and subtitle/language manager. Haven't heard about people complaining about it so far.
I think there's an equivalent, but not sure which is more known.
Mostly media player classic CCCP Media player classic!, it allow me to change the resolution of the screen(number pad) so I like it to use it for Anime. For everything else it Window Media Player, coz it look nice...I didn't update it to WMP 11 for nothing XD