System Idle Process at 99 CPU/Interrupts

System Idle Process is usuing 99 cpu then 91,96,89,95,90, 94, 93, it keeps changing and it's only using 28 K of memory. I used process explore and it's showing interrupts that keep changing numbers in the CPU section from 1.56, 3.08, 4.69, 6.25, 15.39, then back down then back up. How do I find out what the interrupts are? Not very good at looking deep into process explore. Thanks for reading.

 

system idle is supposed to be high, that shows that there is nothing using memory at this time:

http://forums.cnet.com/7723-6142_102-270946/xp-system-idle-process-out-of-control/

you can read this thread for further clarification, but 99 is good for system idle