GE Fridge, Model A3316ABSARWW making horrible sound.

This fridge has a few problems..

Recently there seems to be a problem with the fan in the freezer. Sometimes it doesn't move. Is it supposed to be spinning all the time? Anyway I thought it was so I gave it a whirl with a stick and it started moving again. Seems to stop every now and then even though the fan on the back/floor is running. Only recently it would start making a 'squeak wheel' sound for 10-15 seconds, to end with a horrible lower pitched tire-screeching sound (lasts 2-4 seconds). This seems to happen mostly at night and it happens maybe every 10 minutes. It seems fine now though during the day.

Another issue I'm having with this fridge is that the lowest compartment in the fridge seems to rarely go under 40 degrees. Everywhere else in the fridge seems to go under 40 without a problem. As a result, things I put down there spoil faster, cheese melts after a while, etc so I have avoided putting things in there.

One last thing. I don't know how old this fridge is--probably pretty old. I bought it used and it lasted 18 months so far.

Any ideas how to fix these issues would be appreciated.

thanks