Ipad 2 updated to ios 8.3 and now it's super slow and won't connect to wifi

I recently updated my Ipad 2 to ios 8.3 or whatever the latest ios is, and since then my wifi is almost non-existent (very limited connection) and it is so slow! The only way I can connect properly is if I shut down the ipad and re-start and then the wifi kicks in - but I don't want to have to do that every time I'm using it.

Also, I noticed that when I'm jumping from app to app, it is slow to refresh the screen. I know that I can update to the latest ios but maybe I should be downgrading and restoring it back to the one I had before?

I know my wifi connection is spotty in some rooms in my house and that's always been the norm, but now even in the rooms that never had issues before won't work for my ipad.

Very frustrating. Anyone else with this issue?