Press escape. go to the "controls" menu. that will list them and enable you to change them. To right click on a mac, Control + click.
(that's not the key with the loopy thing, it's on the far bottom left)
if you have a magic mouse, you can configure it to separate right and left mouse clicks to make things faster.
Hope this helps.
As a windows user, I'm entitled to laugh at fact that I have no idea what this conversation is about anymore. Snow leopards and lions...I thought Apple was in California, not Malaysia/Africa. *cough* Excuse me.
As a long time Mac guy let me make a suggestion. Get rid of Apple's crappy mouse and get a real mouse. I have a wireless intellimouse explorer hooked up to my iMac and it works great. Unfortunately Microsoft seems to have discontinued that one. I normally use my MBP's trackpad for normal use but I picked up Logitech 510 to take to minecon last year and it works great too. Both of those are basic programmable four button mice with scroll wheel but if you're a heavy gamer you can get a lot fancier gaming mice too.
edit: forgot to add this
Apple, like pretty much every company on that planet, has used code names for their unreleased products for basically forever. When Mac OS X 10.2 was in the works the Mac media began to refer to it by its code name Jaguar. Apple seemed to like the idea and started to refer to it the same way and has since.