Another idea, instead of running on startup replace all their IE shortcuts with shortcuts to the batch file, and have it set the homepage every time, then load IE. That way you avoid boot > install game > go to browse the net and oh noes the homepage changed.
Ah Ha that too was once my plan. We had an issue with a database program from an nz company called Acclipse at an accountants office. All the computers would only start IE and outlook in safemode when the acclipse toolbar (required for its features) was enabled.
Sorry i mean it would run fine in normal mode, but would always prompt the user to start it in safemode even though nothing was wrong because the acclipse toolbar was faulting on exit without actually faulting.
Anyhow when IE came to update itself via windows updates, the normal internet explorer icons got put back into place and staff stopped using our script icons that cleared the safemode flag then launched the application without them knowing anything had been fixed in the process. So i never bothered doing it that way again for IE which thankfully wasnt as bad as outlook.