Restoring Group Polices to Default

[sUiNeG!bMud]

Hi,

I was messing around with the Group Policy Editor for my XP box and
made some stupid changes which were reflectived in all user accounts,
including Administrator. Now I can't even login to the Group Policy
Editor as Admin to change anything - nor can I get access to any other
Administrative Tools. Is there anyway of restoring the group polices
to the their default? I read some where that their is a file called
Setup Security.inf (or something of that sort) that would restore the
settings but am not sure how to access it.

Any help would be appriciated.