Ok... this is what I understand:
You're typing on your keyboard, and the keys are screwing up. Sometimes you hit A, and it types out Z instead, for example. Some keys don't work at all, others work some of the time. Very possible - it can happen when you spill something on the keyboard, or if you open up the keyboard and tinker around inside.
This is what I don't understand:
Your keyboard problems seem to be horrible at one moment, and not so bad at another. You claim to be typing on a virtual keyboard (I.E.: a GUI inwhich you click the mouse to simulate keystrokes), however, your typing problems STILL seem to be very persistent. A few mispellings, I understand. Some Internet shorthand, no problem. However: "dud not funny now iam using virtual eybard . I'm SERIOUS y r ppl here so ......asses smetims" - eybard? smetims? If you're clicking a mouse to type the keys for you, you're obviously "typing" much slower than normal. Speed is one thing that often causes typers to make mistakes. With mouse clicks, you should be able to easily click each key needed, in the correct order, and even take extra time to think about spelling and grammar.
I'll give you the benefit of the doubt though, and offer you my honest suggestions, even though I think this is a load of you-know-what:
First, if it's wireless, replace the batteries and try again.
Try removing the keyboard plug from the back of the computer, and restarting the computer without it. You should get some sort of warning about not having a keyboard. Replace the plug at that time, and either press a key to continue, or restart again. It may work properly once the computer restarts.
If you spilled anything on the keyboard, take a few Q-Tips, and a few sheets of paper towels. Dip them in rubbing alcohol (note: not vodka, rum, beer, wine, etc.) and swab over the keys, inbetween the keys, and beneth the keys. You can even use an object (thumb tack, butter knife, etc.) to pop off the keys and clean underneath them. If the keyboard is a complete disaster, unplug it from the computer, then dump a generous amount of rubbing alcohol into it, swish it around for a minute, and dump the alcohol out. Let it dry for at least a day or two, until there is no visible traces of the alcohol left. Make absolutely sure that it is not still wet, or shorted in another way before you plug it back in.
If cleaning it doesn't work, try another keyboard. They're cheap. You can pick up a POS for $5-10 at your local computer place. Plug it in, and try it out. If that doesn't work, you either have a virus, or you somehow corrupted your plug and play freature, or somehow installed improper drivers.
If the new keyboard DOES work, than your old keyboard is probably toast, and it's time to give it a proper funeral. I suggest holding a wake, and having them burried on a clear, sunny day with a slight breeze. Ask for a space near a tree, don't be cheap on the headstone, and make sure to leave flowers annually. They like that sort of thing. Oh, and I hope it wasn't a G15 or one of the expensive wireless ones... that would suck.
That's my two cents.