Forgot administrator password

Hello,
I have windows xp professional with service pack 3. I haven't used this desktop computer in some time. I forgot what my password was. I have tried using a downloaded disk to reset the password but it did not work. I have tried going into safe mode command prompt but in only gives me the choice to go to micrsoft xp professional. THere are no choices to go to adminstrator. I have tried everything. I do not want to have to reload the operating system because then I will loose my pictures that I have on that computer. Can any one help or give me some advice. I am very fustrated. THank you