What to do with a non-working CDI (that others have burned successfully)?

I have a couple of CDI game image files (and have had in the past) that seem to burn just fine - no errors - with DiscJuggler. But then when I pop them into the DC, they load up the Sega logo, and just spin and spin (and spin). When asked if other people have had ANY problems with the same CDI's, they did not (they burned the games just fine with them).

The question is, what can I do differently to get these games to burn?

Would it be easier to play with the settings in DJ (although this doesn't seem to help, and doesn't seem as if it would - especially since many of you claim that changing the settings isn't going to do anything anyway)? Or should I convert the cdi to another type of image file (say, Nero/ISO) and try burning with Nero (or whatever)?

I hate wasted time in d/l'ing these files, and in burning the discs, and hate making coasters. There's gotta be something I can do...