It could be malware or something as simple as your computer overheating. It certainly would be worth starting by scanning for bad bugs on your hard drive, though, seeing as how there were problems here due to butthead hackers.
What antivirus/anti-malware programs do you currently have installed on your computer? There are a number of free ones available that, if you're able to keep the computer on long enough to download and install them, will help get the computer cleaned up. Go to download.com (part of cnet.com) and look for programs like Hitman Pro (you get a 30 day free trial with that one), AVG Anti-Virus Free, and MalwareBytes AntiMalware - all good programs.
What antivirus/anti-malware programs do you currently have installed on your computer? There are a number of free ones available that, if you're able to keep the computer on long enough to download and install them, will help get the computer cleaned up. Go to download.com (part of cnet.com) and look for programs like Hitman Pro (you get a 30 day free trial with that one), AVG Anti-Virus Free, and MalwareBytes AntiMalware - all good programs.