I can't use my iSight outside of mac programs

Hi i can't seem to use my iSight whenever i tried using it online for example when i tried to take a picture on facebook through the camera it says it can't be found. You guys might be thinking it's just facebook like me but when i was looking at the Adobe flash player settings google camera adapter was selected for camera and when i changed it to built in iSight it still didn't work for either photo or video so yeah it cant find my camera what can i do to fix this?
The google camera thing is probably from the Gmail video chat download so i could chat with my friend who told me to do it through gmail so yeah.
Help please?
Oh and sorry if i put this in the wrong section i thought this would be the right place

have you tried the usual troubleshooting tips?

I did right after you posted it and nothing.
I think it's because i downloaded that video chat thing for gmail thats what i think could have messed it up. idk how to get rid of it though i type in gmail and nothing when i do search for it on the mac

I found the google video things deleted it nothing then restarted computer nothing then reinstalled flash player and it worked but not instead of iSight it says "USB video class video" oh well thanks for the help if anything goes wrong I'll order the install dvd's from apple to restore mac