Changing User Information

Hello!

I bought a MacBook used, and it was barely every used and everything is in great condition, except I can't seem to change the name on the Home file of the Admin account. I have renamed the admin/username to my own, but when I go to "Home", the name is still the previous owners.

I went to "Users", right clicked on "Get Info", and tried to change the name under "Name & Extension" but I wasn't able to because a box popped up saying I couldn't modify the name because it was needed by Mac OS X.

Is there anyway I can change this name to my own?

Thanks

The best way with a used machine is to do a fresh install of the OS to eliminate everything of the prior owner.