Windows XP Administrator won’t log on

My daughter changed my account from administrator to limited access. She made herself the administrator. When we try to log on the computer acts as though it is then goes to saving settings and back to the log on pagewhere it shows both accouts. I cannot access the internet nor can I change anything do to her changing my account. I’ve tried going to safe mode and nothing works. How can I get Windows to boot up under her account?