Sometimes people in the game get hacked, so here's a few tips.
First off, don't brag about what you have making yourself a target.
Secondly, be cautious about skype. You link your computers together during that time, and it's easy for a hacker to slip a virus in during that time. Only use skype in the game with people you trust.
Thirdly, never accept files from anyone, unless you trust them, scan it ahead of time with your anti-virus.
Fourthly, scan your computer often. You'd be surprised how often things can and slip past your anti-virus, so scan at least once a week, if not daily.
Some free programs:
Malwarebyte's antimalware
spyware blaster
spybot search & destroy
Avast anti-virus
Clamwin anti-virus
Threatfire
Ad-aware
comodo system cleaner
Zone Alarm Free Firewall
Comodo firewall
You don't need them all--using them all will slow your computer down.
Just get one anti-virus and 1 or 2 anti-malware programs and only 1 firewall.
Safe surfing everyone