I don't have a problem with anyone using my PC really. My parents don't get any problems using a PC on their own other than the occasional "how do I do this". They've not ever got spyware or viruses either, you really need to be a bit thick to get them nowerdays...
Really dont enter a currys store, went to pick up my camera from the newport branch. Every customer infront of me had virus issues on their pc, i really felt sorry for the women behind customer service.