There are these factors that determine if you can run other things while burning a CD-R/RW disc:

1. How much RAM you have--the more the better.

2. Does your burner drive have buffer underrun protection (e.g., it has a lot of buffer RAM on the drive itself).

3. Is your CPU fast enough to handle CD burning and running other tasks simultaneously. Machines with two physical CPU's on the motherboard, Intel Pentium 4 Hyperthreading Technology, and dual-CPU cores on one CPU die can safely do this. Note that with Windows XP, only the Professional version supports dual CPU's and dual CPU cores on one CPU die, while both the Home and Professional editions support Hyperthreading Technology.