Cannot access files on 2nd HDD

have 2 hard drives and 2 different installs of windows, for some reason the other hard drive will not boot, but it is accessible. I can access any files on this hard drive aside from the one account i need to access. I get an error saying access denied. I saw a similar post but didnt help me, i tried to right click and find a security tab but XP home all i see is sharing and security, never found an ownership tab. I have also tried to repair windows but it says admin password i type is incorect. Does anybody know a 100% sure way to recover these files?

Thnx if anybody does