Same thing happened to my friend's X5 when I tried to help him upgrade his MKIV to v24.1. The screen went blank and stayed blank for hours. We tried and tried and finally were able to get it to eject the disk. We downloaded the other version of v24.1 (I think the .iso one) and use Nero Ultra Suite 6.6 to burn and it worked like a charm. We didn't have to burn it at 1x, but did burn it at 48x.

I read it somewhere that you may want to use a quality CDR, and not a cheap one. Our first try was a cheap CDR and then we tried the TDK on the 2nd try.