Advertised shortcuts off, then you will want to look at the component Key files.
Removing the key file in a component will stop self healing.
(ie Adobe Acrobat products that attempt reinstallation when My Computer is clicked, this might be the internet explorer plug in, nppdf32.dll)
In some cases I've had some undesirable side effects to removing the key file, like IE not seeing pdf files after the key is removed from that component.
(To see which components are calling out, you can cancel your re-install, and then check the Application log in Event Viewer)
As far as reinstalls for every first time user...
I've had some success eliminating this by placing components from the [AppDataFolder] in the[CommonAppDataFolder] instead.
Hopefully this helps.