Accumulating problems on W8

I'm guessing this is a "performance" problem, but, before I start, FWIW, uninstalled Avast 2-3 weeks ago,

Initially, my problem became slow refresh on Windows Internet Explorer, Firefox, and EM Client. Browser pages would take 3-5 minutes to re-display. EM Client would take 1-2 minutes to open an email. After a few days, most colors disappeared from the browsers. No ads displayed, Accuweather (for example), displays only text and links. Changing from 'Mail" to "Calendar" in EM Client can take 45 seconds to a minute (yes, I timed it). Last 2-3 days, the keyboard is agonizingly slow. Sometimes a pressed key NEVER gets to the display. Sometimes, after a few seconds, I get 5-10 of the key I pressed. Changed batteries in the keyboard with no difference. I've found, if I reboot, the keyboard works fine for 10-20 minutes. Because these problems run across multiple apps, I'm guessing it's W8 and not the apps. Any ideas/ suggestions on troubleshooting.

I'm at school, cannot walk you through this. Download, install, run both MiniToolBox and Piriform's Speccy. Save all logs not on your desktop, rather save all logs somewhere in your Data partition area. Others in the know might ask you to post parts of those logs, and if so, will tell you how to best post them. One of several targets you're looking for: background-running programs and utilities that scan and log, scan and log, scan and log constantly. Also, certain Search and Index functions, certain System Restore Point settings -- might or might not be contributing to this situation.
Before embarking on all of this: you have been and still are making routine full images of your OS and Data partitions onto affordable, reliable, external media, correct?

Thanks for the reply. DLd MTB - file attached. Tried to DL Speccy, but shows in folder as Manage Engine Application Manager.
Full images? Nope. Never done it. Just backup essential data files. Been doing that since the '50s.