Change Default Web Browser

Hi folks,

Background Reading

I am in need of some help, the company I work for have developed a custom web browser. It will be distributed in schools as part of our “safe surf” initiative. The web browser has a limited interface i.e. no address bar and only points to our website which has a directory of “porn-free” websites, which the student can click on. It does not allow students to type in a URL as that way they can access inappropriate material. All websites are pulled from the SQL database, and each website has a rating from 1 to 10. Each student has a username / password which is stored on the SQL server along with a Rating of 1-10. If a student has a rating of 5 then they can only view websites, which have a rating of 5 and below. To stop users from accessing the web from other software via hyperlinks etc they have been blocked by a software firewall.

The Problem

The student will be browsing the web through our web browser however when it comes to popup windows, or windows open in a new folder, Internet Explorer is currently being forced open, which is no use as it will be blocked via the firewall therefore a “page cannot be displayed” error is shown. The default web browser has to be changed from Internet Explorer to our custom one. I have changed all file associations for .htm / .html etc but no luck. I need a solution that will work across Microsoft Windows 98/ME/NT/2000/XP/2003. I know this may be impossible but I could really do with some feedback.

I appreciate any help. - Thanks

Imran