CONSTANT 'not responding' message & freezing

I’m 80 years old so i don’t understand all this new computer language. I do a fair amount of searching subjects via google, and a fair amount of forum participation with a model train hobby.

  1. I am getting this ‘not responding’ message SO OFTEN (every 5-10 minutes)?? I am about to give up on Firefox which I have used for years on my Win7 laptop.

  2. Also when i first log in in the morning it seems to take forever to load Firefox regardless of what site I am trying to visit?

  3. When I leave a subject on Firefox, then go to look for another I am informed that Firefox is already running, so one of the two has to be shut down,…even when i thought I did shut the first one down,…SO annoying !!