I'm 100% with you, except for the bias towards Windows being more insecure.
Sifting through
debian-security-announce archives 2005 lists two entries regarding the kernel: 2.4.27 (fixing 12 vulnerabilities) and 2.6.8 (27 vulnerabilities).
Both items carry the bottom line "We recommend that you upgrade your kernel package immediately and reboot the machine."
The top
twelve Linux machines run on older kernels than that.
If you want to patch the kernel, you have to reboot. That's the same for either Windows or Linux.
And I still don't believe that being Open Source does
per se mean you're more secure. It just means bugs
might be fixed quicker
if the supporting community is big enough.
Still requires a reboot, though.