Windows 10 problems

[Carruthers]

A few days ago my W10 PC started to ask for a password during boot up.
It said that I had used the wrong one and would I kindly use the correct one, or words to that effect.

I have two Hotmail accounts set up and it is obviously trying to use the wrong one.
I've never had to go through this process before, presumably having set up the system at some point to avoid the chore of signing on.

To add further arse ache (sorry) I find that Windows has slowed to the speed of an arthritic snail on crutches.
Firefox, my default browser, takes forever to appear and both IE and Edge aren't much better.

Anyone else experiencing similar woes?

PS Using my superannuated iPad to post this.