i would hope that it was as simple as that, definitly try that, a blank password for admin would be a sweet fix, but just in case its not, try typing in YOUR username in place of administrator and of course your password, hoping your account is also an administrator, ou can get in that way and change the password for administrator once there. If your still stuck after that, as a last resort, they DO have programs that are self booting that will allow you to change the passowrds for any account on an ntfs system. i cant think of its name offhand, but i know a buddy of mine at work has it, if you need it PM me and i will get its name and a place to download it for you
good luck