When Opera 6.02 is installed on a fresh copy of WinNT 5.1 (Home or Professional), there is a chance that you are unable to select it to act as the "default browser" icon on the Start Menu.
To change the "default browser" icon, you would normally go to the Start Menu properties, select Customize, and then select your browser of choice from the drop-down menu. However, a fresh install of Opera 6.02 may not show up here.
To remedy the problem, implement the following registry keys:
This will allow you to select Opera as the Start Menu's "default browser" icon.
Please note, that this does not affect Window's system-wide "default browser" setting. You can have Opera as the Start Menu's "default browser" icon, but if IE is still the system's default browser, a URL entered in the run dialog box will still bring up IE.