PROBLEMS WITH ZA 5.5

Don't know if this is where I'm supposed to put this or not. My system is HP Pavilion desktop with windowsME as op sys. I have IE 5.5 for my browser, and will upgrade to IE6 as soon as I can get this issue resolved. I have the following security programs installed:

ZA 5.5
s-t-i-n-g-e-r (I use as a last resort)
CWShredder
Ad-Aware SE personal
Spybot S&D
AVG Free
SpywareBlaster
HJT

The problem that I am having is that ZA will be going along fine, and then all of a sudden the program alerts screen will go blank. This has happened twice, both times after scan disk and defrag. I use these 2 in safe mode. What I'm wondering, is there something about using ZA and AVG together that is causing this, and if so, what can be done about it. I know that the email scanner in ZA and AVG are not compatible, and I have the email scanner and the AV in ZA turned off. I was just wondering what the problem could possibly be?