Maybe you have too much in your start up not needed at that time? they will stay in your programs, but not loading at start up, which slows it down.

How do I know what to keep and what to get rid of? I know there used to be a list (I think it was for Win98!) that I used years ago, but I don't remember the website. Do you have a link that I can find out what to delete and what to keep?

Only, get rid of things you downloaded, things you know did not come in your OS=operating system from Microsoft or mfg. of your PC etc. ( to play it safe)

You don't need things like iTunes or Skype or Adobe Reader, etc., starting up unless you actually need them. If you don't know what something is, do a little homework using Google.

I have a problem with my screen catching up to my typing and scrolling.
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I have Win 8.1 and Firefox.

You mention "typing and scrolling" but don't state specifically where you're doing this "typing and scrolling".

Does the lag occur in "Notepad", "Wordpad", "Word", "IE", everywhere?

Or is it only in "Firefox"?

If only in Firefox, I might try something like this:

(1) "Restart with Add-ons disabled..." (Under "Help")

(2) If the lag goes away, I'd start Firefox normally, and manually disable ALL add-ons. (Tools->Add-ons->Extensions)

(3) Re-enable them one at a time, testing to see which one reintroduces the lag.

That's probably only applicable if it's a Firefox specific problem though.

The site you were trying to recall may be the one below.

Another previously popular site, answersthatwork.com, does not appear to be current with W8/8.1.

DA

Here is a link that might be useful: Pacs-Portal

Thanks! Chugger, I did the restart with add ons disabled, it works great, but now no matter where I go I get popup ads before I can see any video or website, whereas I never had this problem before.

Are you using "Adblock Plus"? If so, probably it was preventing the ads before. Since it was disabled along with the other extensions, you're just seeing how good a job it was doing. :)

I suspect you're close though, just need to restart Firefox normally, go into extensions (Tools->Add-ons->Extensions) and figure out which one is causing the problem. By selectively disabling and re-enabling them I mean.