Use Regedit.exe and search for NoBrowserOptions and remove it.
It is most likely to be here (but not necessarily)
HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet
Explorer\Restrictions
If you are unfamiliar with Regedit, then ensure you know how to
restore your Registry in case of error and it is a good to export any
key before deleting.

Check the startup (Start-Run-MSCONFIG-Startup tab) for any unknown
items if it is reset on reboot.

You might try this snippet 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" '

...Alan

I'm having this same problem. Somehow the home page
default has been hijacked. I'm able to go to my computer>
control panel> internet options and change the home page
page manually to bypass the default (porn site that
continuosly loads to lock up and installs all sorts of
crap on my desktop) but if I reboot and try to use the
explorer shortcut on my desktop, it loads the porn crap.
This problem is pretty serious and I have spent 2 days
trying to resolve the issue, including installing all the
latest MS updates.