It might have not been a virus but it was some kind of hard drive thing that kept the mac in a loading state (kind of the white screen with thing swirling in middle) and never changed and kept making that sound when it turns on (kind of computerized whizzing and then a hummmmm) at regular intervals and we could only turn it off by taking out the battery and we have no idea why it happened.
And sorry forgot to mention but I have a MacBook laptop.
What you have is not a virus. Most like a corrupted PRAM and/or hardware cache file.
"kind of the white screen with thing swirling in middle" - do you mean a grey screen with a spinning gear?
"kind of computerized whizzing and then a hummmmm" - do you mean a "bong"?
Anyway, I suggest you do the following:
Reset the PRAM and do a SAFE BOOT
At power up, immediately hold down the cmd-opt-p-r keys and keep holding them until you hear the third bong and then let go of the keys and then immediately hold down the shift key. Keep holding the shift key until the grey screen appears with the spinning gear and then let go. This boot will take some time as a lot of housekeeping goes on (cache files are deleted and rebuilt, file system is checked and repaired, etc). This could take between 5 and 10 minutes but eventually you will get a login screen with "safe boot enabled" in red. At the login screen, hit the back arrow button on the screen and select restart for a normal boot.
If this doesn't correct the problem you may have a hardware problem.
Also, if you run into this problem again (continuous recycling), you don't have to remove the battery. Just hold down the power button for about 10 seconds and the MB should shut off.
As far as your iLife restore problem, I can't help you on that since you are missing one of the restore DVDs.