potentially rootkit-masked files...?

[robot_takeover]

i did search for them manually, and found them, but could not delete them when i searched.

[jholland1964]

Well this problem evidently has popped up for many, because my search this evening has produced several results...yesterday and day before...none.

I believe now, unless your computer is running very badly, that these ARE false/ postives results. I have just found this on numerous sites;

"Because of the technology that Spysweeper uses, alot of times it alarms you of potentially masked rootkit files. Typically this is nothing to be alarmed about as it only looks for differences between the disk and what Windows reports back. This is not definition based.
There is a setting in the shield tab to check for root kits, untick this option.True rootkit detection is far beyond an app like SpySweeper"

Add the above remarks to the results of your Sophos Rootkit Remover I would say that in all likelyhood you DO NOT have a rootkit on your computer.
So unless you are having major problems, I would ignore this warning and follow the directions given in italics above for NOT having Spysweeper check for rootkits.