The sound makes occasional popping noises, the sim freezes, loading a flight
once after clicking "Fly Now" took 15 minutes to load.

Try running it with your virus scanner off, and report back. My
computer has been slowing down to a crawl (I can't even access
accuweather.com any more) and I traced the problem to the AV software.
Even a fresh install didn't fix it. Apparantly, there are so many
viruses and the scanner is so inefficient that it takes up all the clock
cycles. It also pretends that it's the other program's fault (i.e.
running Process Explorer, it is the "other" program that is reported as
using all the clock cycles).

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.