To best thing to do with the Windows XP ICF is to turn it off, as it does not filter and block outbound connections. Just download and install one of the following free firewalls - kerio (
http://www.kerio.com/kpf_download.html), outpost (
http://www.agnitum.com/products/outpostfree/index.php), and You will notice a huge difference.
Next, download this software:
*
http://www.lavasoftusa.com/support/download/ - update and scan;
*
http://www.safer-networking.org/en/download/index.html - update, scan, immunize;
*
http://80.237.140.193/downloads/hijackthis_199.zip - turn off all the software that You can (instant messengers, browsers, etc.), scan, post here the log.
Regards.
EDIT
Furthermore, You cannot forget about updated antivirus (I recommend Kaspersky) and updating Your system with Win critical patches (Windows Update...).