Unable Scroll One Line At A Time IE8 / Firefox OK

I run Win 7 32-bit and IE8 on my laptop. Until approximately two days ago I could control scrolling in My Favorites, with ability to scan one folder or it's contents at a time. Now, unable to control this action, and after the last visible line, if I try to go further down, the scroller automatically starts over at the top. A similar problem occurs on several websites, but always occurs with Favorites in IE 8. When using Firefox, I can control the scrolling without any problem. I remember that this issue came up about a year ago, when many of us were trying to understand what was going on; unfortunately, I don't remember how it was fixed! I've reset, cleaned cat-hairs from, and changed battery in mouse - not the problem. Windows has added a ton of recent automatic updates and I think one of them is causing the problem. I can view a number of them, and see they are related to Win Office, but due to inability to scroll down any further, I can't view those which may be related to IE.