how do i reset macbook pro 13" 10.6.8 (mid 2010 startup disk is full
I got my macbook pro 13" (mid 2010) (10.6.8) back from an ex and now I am stuck with his user login and I don't know the password. When I try to reset at startup by usingCommand 'O' I =get the message "Delete some files0your startup disk is full. I no longer have the startup discs, so I need help resetting.
THANKS A MILLION
MacBook Pro, Mac OS X (10.7.4)