Are you sure it says that or this:Windows Xp Policy Software

The policy software means that someone like a parent or teacher or boss has removed this option from your use by using the xp user policy options....

Saying that there is not much help that can be given for that.

If it in deed says that some Police software is in control...it is one of two issues...
1) it is the real thing and there is nothing anyone can do to help you because that sort of software is basically non hackable and is probably coded to shut the system down on trying and thus rendering any attempt to by-pass it impossible.
2) That this is a new malware/spyware trojan or virus program interfering with your usage and is so new that there is no information out about it....as such I would not recommend that you do anything or try anything for a few days as it may cause more harm than good as it could be attached or programed to do just about anything...New spyware/malwre viruses and trojans do not have much unexposed life span before it is in someone else's computer and then fixes will start to appear.

You can always do a reformat and system installation to clear up any issues like this as a final avenue of last resort.