It is possible that your MacBook's battery has expanded and is interfering with the keyboard and trackpad. Try the following steps -


Shut down the computer.
Remove the battery (I am assuming you have a user removable battery. If not, disregard this post.)
Connect your power adapter.
Start up the computer.
Test using and see if you still have the same issue with [url=http://www.acompatible.com/category/2-keyboard]Laptop Keyboard[/url] and trackpad.
If the issue goes away, check the battery for expansion. Replace the battery.

Best of luck.