I spend a lot of time downloading pdfs & saving them in edited form
to data folders. I have started to experience frequent instances
where my Dell Latitude D630/XP Prof works just fine but will
suddenly stop responding & freezeup, requiring a reboot to recover.

The Event Viewer shows that Symantec AV was in the process of
running or completing a scan at the time these freezeups occur. I
have configured the AV to scan ONLY on incoming emails but it
continues to run these scans. I have come to the tentative
conclusion that the AV is causing my problem but I have no idea how
to disable these unwanted scans without uninstalling the AV.

Here is the most recent Even Viewer log:

Date:10/30/08 Source: Symantec AV

Timme: Category: None

Type: Information Event ID: 2

Description: Scan Complete. Risks: 0 Scanned: 804
Files/Folders/Drives Omitted: 0

The next earlier log item:

Event ID: 14

Symantec AV services startup was successful.

There are far, far more files on my drive than 804, so this is a
mystery as to what is scanning & why. And how do I prevent this from
happening?

Thank in advance!

Jack