SpywareCatcer detected "BackWeb" when I rebooted my computer. How do I know if BackWeb is being used for malicious purposes or if it's just something that's installed on my HP computer?

This may help:

http://h10025.www1.hp.com/ewfrf/wc/generic...cname=c00061410

Backweb is an application used by some manufacturers to handle updates; whether you wish to use it is optional. You can configure your firewall so that it always "asks" before allowing Backweb access to the internet.
Regards,
John