mail is trashed

when i try to launch mail from the dock, it bounces a couple of times and then nothing. just a picture of my desktop on the monitor. the only way to make it quit is a force quit. you can't use shortcut keys. any ideas on how to fix this? everything else seems to work. on a brighter note i was able to fix the "frozen volume problem" with resetting the PRAM. to be honest i'm a little disappointed with the trouble i'm having. this imac was purchased in january 2007.

Does Mail launch from within the Applications folder itself? I would try this.

If it does, drag the mail icon OFF the dock (it'll poof as it disappears), and drag the Mail icon from the apps folder down to the dock. It'll automatically create a new alias in the dock for it.

i've tried that. any other ideas??