Sometimes I just move the highlight bar away from the cdrom, wait a few seconds, re-highlight the cdrom and press enter again.
Cheap drives like the Toshiba XM-1402B can't read CD-RW, and when there are read/timeout errors, the "disk reset" sequence used by Smart Boot Manager doesn't work right. I ran into this several times when I tried installing WinXP direct from CD -- I just couldn't get through the installation. I've been meaning to revisit this code and see if I could do anything about it, but there are a whole bunch of other projects I'm working on.
There have been no updates to Smart Boot Manager (on SourceForge) in over a year, so I'm guessing it's an abandoned/stable project. Ah well, my 1402B drive isn't a great unit to begin with. It was a huge bitch creating an El-Torito boot-cd with the correct DOS drivers, just to get Win98 installable from CDROM. No wonder those drives are easy to find in surplus hardware stores. :o)
I've been planning to hook up a Sony DWU-14A (DVD+/-R/RW) powered by an external enclosure, just to test the firmware's compatibility. (Again, my test is WinXP or Win2003 install from CD). If all goes well, I'm planning to install a notebook DVD/RW drive in the next few months. Hopefully both drives will be compatible with the existing code. If not, I'll have even more hacking to do..
I wish I had better news.. but right now, I think the most painless solution is to try a different drive.