With my linux box I can do the following to watch interrupts live:
watch -n1 "cat /proc/interrupts"
Is there a way to do this on Windows systems, especially Windows 7?
I can only speak for XP, which is what I have.
On XP, I don't know a way to watch them real time, but there is the next best thing, which is logging the events for a time, and then looking at the produced log file results.
The program to do this is RATT - it's a Microsoft produced tool, that's really light weight, and clearly aimed at developers. Not that tough to use though, and it does the job.
(Used it very recently myself to diagnose a problem with excessive hardware interrupts constantly taking 25-40% of my CPU processing power. Helped me identify a defective driver that was sending insane amounts of hardware interrupts, and fix the problem. )