trouble with Apple ID and Facetime on Ipad

The issue I have ultimately is trying to use Facetime on my ipad mini. It is many years old, and I don't usually use facetime, but now need to.

It is not working however, when I am trying to use it with wifi... I don't have a data plan.

So... first thing was to try and update the system, which it needed. It won't let me do via wifi, so now I am having to log into iTunes on my PC. More trouble: my apple ID login, continues to say that it there is a "server error," and cannot login. I tried to log into Icloud too.. and hothing.

I've reset my passcode, so that should be fine.

Help!!