Well... I suppose you could modify the permission for that key giving users read only access. Then give "system" full access if it needs it. It does need it in *most* cases, right?

But... all someone would have to do is gain "system" privledges... and run regedit to modify the settings... System privledges is not very difficult to get either... especially if you are admin on the box already.

This is software that is going to installed on boxes out of your control?

If in a domain environment... you could use group policy?

One of the ways in which you can protect your Windows registry is to configure permissions. You can do so by opening the registry and using the Permissions option. An alternate method is to set the registry permissions using Group Policy. You can easily accomplish this using the steps outlined below.

1. Open the GPO you want to use for implementing registry permissions.
2. Expand Computer Configuration | Windows Settings | Security Settings | Registry.
3. Right click the Registry and select Add Key.
4. Locate the Registry key you want to configure permissions for. Select the Registry key and Click OK.
5. Configure the appropriate permissions and Click OK.
6. Make the appropriate selection from the Add Object dialog box and Click OK.
http://www.google.com/search?q=group...ry+permissions

Google's first link

You would have to give the user *some* way to control it. What if they want to uninstall it?