Playing .avi videos in iphoto

Before I installed the latest snow leapord OS I could play .avi videos right from iphoto. Now I have to right click, open file info, find the video, click on it, click again to play and click again to view in full screen. Is there a setting that I missed when upgrading my OS?
Thanks for any help.

Snow Leopard isn't the latest OS.

But apart from that,it sounds like you need to upgrade your Flip4Mac WMV Player and Perian if you haven't already.

OK, it's version 10.7.3. I've never heard of Flip4Mac or Perian. I'll check them out.
Thanks

That would be Lion. Hopefully the two (free) programs I mention will sort things out for you.

I downloaded both of those programs. I played with the flip4mac settings and read the user guide and it did not help. I also downloaded the nice player from perian and no change. What settings for these programs should I use.
Should I download the latest iPhoto from the mac store?

Have you restarted the machine since doing this?

Twice. I downloaded the latest update for Quick Time Player, also.

I just restarted my Macbook and it works!
Thanks for the help!