I've never used iTunes or anything, personally. [[ Mostly I've used Windows Media Player, Winamp, and Realplayer. ]]
I like Winamp best because it plays all file types, even the weird .mp3 extensions that Windows Media Player .. refuses to play for some odd reason. I have lots of video on my computer but most of the time I only use audio files, so .. >_> This works just fine for me.
Windows Media Player I'd rather just use it for videos, since... -Winamp- refuses to play the actual video. Why? No clue.

But since that's pretty rare, it's not open all that often.
Realplayer.. I just didn't like.