Laptop Keyboard Not Working

Hi,
Recently my laptop keyboard started acting strangely. For example, pressing backspace would highlight text, enter would bookmark webpages etc. This fixed itself after I restarted my computer a couple of times, but ever since then the up and down arrow keys have not worked. If I use the On Screen Keyboard, those up and down arrow keys work. I don't know if this is an indication of anything. I uninstalled keyboard drivers and reinstalled them, but that did not work. I removed the keys and attempted to clean them with a Q-Tip, that did not work either. I would appreciate any other suggestions or ideas to solve this issue. Thanks in advance for any help.

Magmaniac