I CAN'T PLAY AVI FILES YES AUDIO NO VIDEO

I downloaded VLC to play some .AVI videos I had from the same web site, after I made a lot of tentatives with a lot of players (DIVX, NANDUB, Windows M.P.10, Nero Show Time ...)
With some videos it works for the others I can have only sound.
I opened the avi files with Hexedit and I found this :


OGG 5 9. VIDEO VP618

could you help me to play that files?

VP61 is the fourcc for the on2 vp6 codec. Get it at on2.com