I could be wrong, but it sounds like some of the help content is online, so when your friend is offline they are only seeing whatever is stored on the computer + whatever it has cached. I tried disconnecting my machine and looking last night, but it looked the same to me - though maybe I had the "mountain" image cached locally, or had a "full" install of Vista. (Depending on the type of laptop PCW may "slim down" the Vista installation to save hard disk space).
If this is the problem you refer to in "Law", IANAL but suspect that it isn't really a PC World problem (unless your friend has a super-duper "fix everything" package). Though obviously PCW are full of the brown stuff and their "guarantees" aren't worth the paper they're written on. And yes, it does sound like BS.
Do they have the same lappy on display still? Ask them to turn off any net connections and clear any cached files, then check the affected pages in store. If it works then it's your laptop, and they should be prepared to swap it (though may not be prepared to copy over any of your friend's documents etc); if it displays the same symptoms then my supposition may be correct.