Help please on INF:AutoRun-AA [Wrm]

Now my dear Avast! blocked it on this computer which is awesome, however I have a few issues.
1: My parents laptop which they use for business broke a few days ago, it asks whether ou want to start windows normally or launch startup repair, both eventually just lead back to the same page asking which you want to launch windows never loads, this is after failing to update a few days ago it’s a Dell and Windows 7. Is it due to the same virus, is that how I got it on my netbook? Because I never download things etc. it’s a shared internet connection through wireless.
2: My netbook which has Avast! blocked the worm as soon as I opened Facebook, I’m really careful not to click on adverts of dodgey links etc on everything because I’m paranoid as it is, however my PC has Norton antivirus which is the same as my parents’ laptop. Should I leave it switched off?? Haha I don’t want to spread it.
3: Where the hell did it come from?!?!
-Priority to number 3 please I’m rather confused if I can find out where it came from it would be easier to avoid.

Please follow this topic:
http://forum.avast.com/index.php?topic=53253.0

Attach all logs here.

I don’t need to know how to clean it my parents laptop wont turn on and my netbooks fine…I wanted to know if that was what was affecting my parens laptop and if it was safe to turn my PC on…

windows update defender files sometimes have signature avast detects those

I’m a bit of a computer der der so I don’t really know what you mean by that, but I can tell you windows defender is off lol and I haven’t done any updates on this recently. I really just want to know if this is whats wrong with parents laptop which died first after not being able to update just going on for days and days on end up update one of 6, they left it plugged in, then eventually just turned it off held the button and turned it on and voila it’s dead. It’s fine because avast stopped it on here, but also how do you get them like from spam emails and stuff? Im more asking for my mum seeing though she doesn’t have access to a computer now apart from mine.

INF:AutoRun usually spread by removable media… like this one
http://www.f-secure.com/v-descs/worm_w32_autorun.shtml

Why you parents computer wont start… impossible to say unless you find out whats in there…if anything at all
computer virus usually want the computer to work… so the virus can do the work it was designed to do

Well I have no disc drive on here so it must have come through my memory stick which i only use at college. aaargh. now i have to tell them. okay thanks a lot =]