It does sound suspicious if they say you have to run some scan or be reported. Sounds more like a social engineering scam than anything malicious. Just someone out to get money from you by selling you a "removal service" for fake threats.
Still, it WOULD be a good idea to upgrade to SP3. You should have done that when it came out, but in cases like this, better late than never certainly applies.
I have a Dell E520 Windows XP sp2 desktop. A long time ago when the Dell forum changed some of the users setup their own forum the Dell Unofficial Forum. I haven't been there for a long time. Well any way I just got an personal email message from someone there saying Take Measures Immediately! That my pc was sending out spam and to run their scan and pass or they would cancel my membership and report me to ISP. I started running the scan but then thought better of it and ended it. It looked kinda fishy and was comming up with a lot of Trojans-email. I ran MBAM and my NOD32 and they didn't find anything. Would they find email trojans?
How can I tell if this was legit?