Well, i don't think anyone here can do that. Please look there:
http://securityfocus.com/
select 'Vulnerabilities' and 'Starforce' in the vendor pulldown. If that has frightened you enough ;-), choose 'Microsoft' to get a "real kick of paranoia".
So - IMHO - everybody who is really serious about security would never connect a Windowx XP system to the internet and visit dubious sites with Internet Explorer.