XP:2/Question Marks Over User in Properties

Good morning,

Thanks for settling me down last week when my desktop's power supply short-circuited after a hardware install. All is well. It didn't fry anything other than my nerves and the inside panel.

On another topic, before I descend into malware removal hell, I need an expert opinion on whether or not this is legit software or not...

I've noticed some files in our fam's Dell Dimension (2002) MS XP2 registry and on our network that seem strange... All of my folder settings are set to show hidden files and encrypted files in blue. On a quite a few folders named HKEY_USERS\S-1-5-21-3504575040-3360622261-3411146076-1018, the owner listed in the properties tab has two question marks over his head. I cannot delete or alter these files. Is this just a cutesy MS XP thang to note that the user is unknown or somehow generic?

Also, I found my recycling bin out on our network with files named the same way. I couldn't delete them. The files were logs of code I couldn't decipher. The folders had the same joker face on the user icon.

I have antivirus software that hasn't found anything. I uninstalled XP SP3 and my recyling bin and network folders disappeared from the network drive. My recycling bin started behaving again, but the joker folders are still sitting in my registry.

Thoughts?

Thanks,
KC