Internet Options & SPYBOT

[DougCuk]

The registry key that Spybot can set is called NoBrowserOptions - the values are 0 or 1
The NoBrowserOptions key would show in the righthand panel of Regedit.
If this key doesn't exist then either Spybot didn't cause your issue or you are looking in the wrong location.

The "No restrictions" "Restricted access" were just my descriptions as to the meaning of the 0 or 1 values

In Windows XP this key is located at:
HKEY_Current_User\Software\Policies\Microsoft\Internet Explorer\Restrictions\
Not sure if this location is the same in Vista.

It may be safer to reinstall Spybot and use its interface to check and change the setting.

There are also infections that can disable Internet Options - but not sure what method they use.
Scan your system for infections just to check this is not the cause of your issue.