I assume you mean Tools | Internet Options.
Close IE.
Open Regedit.
Find the value NoBrowserOptions and remove every instance of it.
It is most likely (but not necessarily) to be here:
HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\Restrictions
You might try this from Mike Burgess first if you use SpyBot:
'Did you by chance run SpyBot's Immunize feature?
If so, you can unlock by unchecking the option to "Protect IE Control
Panel".
See
http://forums.spywareinfo.com/index.php?showtopic=6748
--
Frank Saunders, MS-MVP OE
Please respond in Newsgroup only. Do not send email
http://www.fjsmjs.com
Protect your PC
http://www.microsoft.com./athome/security/protect/default.aspx
http://defendingyourmachine.blogspot.com/