This is a Corporate PC. we need them to make certain changes IE software etc but We do not want them to change time/date......... Not on a domain or anything like that at all......
What changes do they need to make in IE on a regular basis? Do they really need admin rights to be able to make these changes? A couple of suggestions.
Don't give them admin rights unless they absolutely need it.
Do they have their own accounts or is there a common account in use?
Personally I would create a new account - then using Local Security Policy > User Rights Assignments assign that account to the "Change the system time" and remove the default "Administrators" group permissions but leave the Local System. (Bit messy but if they need admin rights elsewhere it will have to do) this will have to be done on each PC.