Should Firewall be blocking these "intrusions"?

For the past several weeks, I’ve noticed a lot more hard drive churning when booting up and when opening most of my applications. No other abnormal behavior. I’m using a PC with XP Home SP-3 with all critical updates installed. 512 Mb RAM, 80 GB hard drive with 30 GB free. I’m connected to the internet with a 1.2 Mbps DSL connection through a combined modem/router.

Today’s activity consisted of waking up the PC from hibernation, opening Firefox, reading web based e-mail as well as checking for some listings, and opening Thunderbird and reading some USENET news text-only postings. McAfee’s site advisor apparently needed my permission via Defense+ to do some update process, which I allowed.

I’d appreciate it if someone would examine the attached Firewall log for the above activities and tell me if my Firewall is apparently blocking valid intrusion attempts, or is mis-configured and blocking things that should be allowed. If so, could that be responsible for all the hard drive churning?

For the record, I also did a full scan (found no hits) with MalwareBytes and with Avira’s antivir, both updated yesterday.

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