With most burning sofware, you have the option to burn on the fly.
Depending on the software the term is alittle different.
With Roxio, you have 3 options:
test (no burn just checks integrity)
test and burn (check integrity - then burns) - slower
burn (just burns - no check) - fastest
Since Nero atomatically burns on-the-fly
Try dropping your burn speed to 24 (since burners rairly burn at max speed), go to your "burn tab" in preferences and uncheck everything but "write".
See how this works. Hope it helps