So I know that Start will end a program, but there's one problem - it doesn't work during pop-up dialogues. Is there a way to terminate it if I accidently made it pop-up repetetively?

For emergancy, click the home button and close out. If it doesn't allow you, click the power button and then home to close out.

Well I can do that, but the problem is that if I haven't saved, it will get rid of my progress. It's really too bad that Start won't kill a program if it keeps doing this. Trojan horses?

This happened to me once. I just had to press home. It stunk.