Why does Internet Explorer 7 freeze when accessing the Internet, Intranet and Restricted zones?

This is a protected mode feature of Internet Explorer 7 which is available only in Windows Vista. Please refer to the steps below to disable the protected mode feature.

1. In Internet Explorer 7, click the  Tools tab.

2. Select Internet Options.

3. Click the Security tab.

4. DeselectEnable Protected Mode (requires restarting Internet Explorer). 

For more details of the feature, please refer to the link below.

http://www.microsoft.com/windows/windows-vista/features/IE7-protected-mode.aspx