have a message i am worried about

i just went onto broadband, and think i got q virus, id followd all the
instructions, but am now left with this.......a black box comes up
saying...C:\Windows|System32\cms.exe then in the box it says.....updating
windows shell files....but nothing happens......then a page tries to
open.....msn.com, but it doesnt open...can someone advise me wot to
do.........bear in mind i am also blonde and females, so please be simple LOL
Jayne
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