The only other thing that I've done is change my firewall software.
I use Bullguard.  I had to use the Custom Security settings for the
Firewall, but set it to always allow pythonw.exe and python.exe access
to all ports.

A colleague of mine is also running XP and ditched IDLE because it kept
crashing.  I explained my reconfiguration of the firewall to him
yesterday but he hasn't implemented my changes yet so I can't report his
success/failure.

Notepad++ is a great editor to use with Python; it is Python-aware (and
it's free).  Another colleague uses it along with "print" in his code
for debugging.

Finally, our computer scientist recommends using Linux only.  Apparently
that solves all problems?