Not come across this one before, very strange!
Xp has it's own firewall, and needs to be turned off if using a third party one, such as "Zone-alarm". AVG works fine with AOL and is also recommended. Zone-alarm is stated as causing problems with AOL and by their help line, though many people do use ZA/AOL without problem.
AOL also scan all email, incoming/outgoing for virus so that none will get through to you by mail. But you still need a standalone antivirus on you system for general surfing and checking of floppy's and Cd's prior to use.
Try disabling ZA while you write an e-mail, see if that helps, or, if XP's firewall is enabled, turn that off instead.
If this does not help, then please post back, we can go through a couple of other methods of rebuilding the graphics display of AOL. Regards. j.