First Question-

I got an xbox 360 from a guy off of craigslist and realized later that I need to change the email address to my own.

I already know how and where to go to change my email account, but I have another problem. When I go to change it, I need his password for his email account and he won't give it to me (I tried to call and ask and he said he understands my problem but he doesn't want to give it to me). I do understand why he doesn't want to give me the password, but now I'm stuck.

Is there any way to get the email changed without his password? Do I need to call a certain number? I'm at a loss.

Second Question-

Is there anyway I can change my gamer rep? The guy I got it from was kind of an idiot and trash talked a lot of people. I don't want to be known for that.

This is why you never use one password for all your accounts.........

You need access to the system dashboard, so you should not need his password for this. Do the initial setup and it should clear out everything.

http://forum.teamxbox.com/showthread.php?t=409569

Barring that, could you take the unit to his house and have him change the password for you? That way he does not have to tell you what it is. Heck, you might even ask him to do the factory reset if you have to use the password to get to the dashboard.

Will this erase all my downloads and save files? For example- DLC, Minecraft, Games saves and the lot? How can I save those from being erased?

It will erase everything on the Xbox. If you have an account with Live, then whatever is stored on those servers should still be attached to the account if you don't delete it.

However, if it is on the box, then it is erased doing this.

See that's the problem. I don't want to lose everything. And all the stuff is on his email.