Click the screenshot of the splashscreen to see the other screenshots. I didn't see a preference for it to not answer, but I did see one to put the popup at the top or at the bottom. I don't know if that would resolve the problem you're having now or not.
The application System Panel has the ability to "Freeze" (and thaw) an app. I haven't tried it, but supposedly it prevents an app from running without deleting it. If you DO want to use the app, you'll need to go into System Panel and let it run again.
If you've rooted your phone, get Root Explorer (etc) and go into /data/app/. Find the super caller id .apk file and rename it to *.apk.bak or something. When you want to reenable the app, rename it back to *.apk