Laptop Keyboard not working properly

Hello,

I have had a Dell Inspiron N5010 for roughly 2 years and have had multiple keyboard issues.  About  6 months after I bought the laptop, the keys started working incorrectly.  For example if I pressed the "I", an "H" might be typed instead.  It started off with just one or two keys and then spread through to involve around a dozen or so different keys.  Since it was still under warranty, I had the keyboard replaced, and it worked fine for about 6 months until the same problem started happening again.... only worse.  

As I'm writing this (using a different computer) the problem involves over a dozen keys and where as the first time I had the problem with certain keys, the problem was intermittent and the keys sometimes worked.  Now, the problem keys almost never work, and instead of typing a letter and the keyboard just printing a different letter, typing a key might actually change the settings on the computer.

For example, Pressing "I" turns up or down the brightness, "H" can sometimes change my monitor settings, "Backspace" prints the "[" and so on.

For reference, I plugged in my desktops USB keyboard to my laptop, and everything works just fine.

WHAT DO I DO???  Is it possible that I really got TWO defective keyboards?

I tried calling a dell representative who was extremely rude and unhelpful, and basically said I can spend a couple hundred dollars either sending it in to get if fixed or even more money to have someone come down and fix it.  I feel like the computer has never really worked properly as the problem just keeps returning.  I already went through all the keyboard diagnostics with a different representative and the computer says the keyboard is functioning.

At this point, it seems like Dell just sent me a product whose defects became apparent after a few months.  After the problem was supposedly "fixed" it just returned with even greater affect after my warranty was up and I was no longer able to get it fixed without shelling out hundreds of dollars.

IF anyone has any ideas on how to fix this or what I can do, it would be greatly appreciated!!