Keyboard acting strange

I must have mistakenly hit a few keys and have changed some setting on my keyboard. Now when I hit the tab key I get a letter (I cant type it because of this weird keyboard but it is the letter in between the tab key and the w). When I hit this letter (worth 10 pts in scrabble) it functions like the tab key. Also when I am in Safari, if I hit the enter key I get a message asking if I want to turn on "caret browsing". No matter how many times I ask it to stop showing this message I keep getting it. It says that F7 turns Caret Browsing on and off but I have presses them repeatedly and nothing changes. I am not sure if I am posting this in the right place but it is driving me crazy. I have tried restoring defaults for the keyboard with no luck. Thanks, Carla