rufioh- Not all of the viruses are equal. You start out as a fairly useless basic virus, and all of the enemies are better than you. Then, as the game progresses, you earn upgrades that give you an advatage over your opponents. Its basic Game Theory. If you need that spelled out for you, its a wonder you even managed to turn your computer on at all...
If you want a challenge play Nano war, it is similar to this but much harder. Its been around for ages- and it has badges- but somehow its never mentioned.
Reallywierd- thats just an enermy tactic. They wait until they have enough resources to defeat all your forces; I think they call it a retalliation wave. If the game freezes it's jjust becuase your computer can't process that many ships. Its no glitch.