Very definitely the best player for Mac OSX is
VLC - (click on link) _ (choose nearest mirror site). VLC is a very reliable player. If VLC can't play a video file then I trash the file. VLC can also be used for video & audio streaming.
But VLC will not play realplayer files. But neither will any other program except for RP.
Also see tips about video downlding from here
Movie download issues
Sorry birdy I didn't see your post reply.
The forums are having some technical problems at present.
**Replies to posts aren't working at the moment.
Reply by PM will work. You'll see an error page but the message still goes through.
Else, start a new thread titled "your original thread - merge".
A moderator will merge threads when they get the chance.