Computer Help Please?

I use a high end Logitech mouse. The rechargeable batteries in it last 2 or 3 months (maybe more - it is long enough I forget the last time I changed them.)I almost always turn the mouse off at night since I believe the wireless communication runs all the time and it probably the biggest draw on charge.I don't know but would guess that addition use (mouse clicks, etc) don't make much difference.

Last fall I did upgrade but after a couple of weeks with little slownesses (that I might have imagined) and a few things I didn't like in the interface I backed out.That went reasonably well actually except for a couple of programs.I will go to Windows 10 as the free upgrade starts to run out.