hey guys, brand new here so wanna just quickly say hi!

I already have an issue! I recently purchased a nexus one that was already rooted and the guy gave me some "tips" which i clearly didnt understand. I have something called metamorph. There were some folders within it that app called "droidzextended" or something along those lines. There was something to do with gmail in there and once clicked it took away my icon. I decided to restart the phone and now its stuck on the begin screen before the animated screen. I have access to the bootloader menu but i dont know what to do from there. I believe he did have a back up of some sort. HELP!