Learn to use a debugger!
First step out of the box, using F12 on your page, I get a syntax error on line 37. Which is:
pic.onmouseout = doMouseOut:
You have a COLON there, where a SEMICOLON is needed.
Fix that one error and it works.
If you haven't learned to use a debugger, it's past time. Just hit the F12 key in your browser (for Chrome or MSIE 8+) and look at the CONSOLE tab to see your errors. After that, you can start to learn all the really powerful features of the various JS debuggers. I prefer Chrome's, but any of them will do.