I too am having the IE scrollbar problems after
installing the Cumulative Security Update for Internet
Explorer 6 SP1 (KB824145), but there's also another
related issue that appears no one has noticed. If you
right-click on the scrollbar, a small context-menu pops
up indicating your scroll options. Selecting any of them
seems to work, but then the same context-menu appears
immediately afterward. If you then click another choice,
a different context-menu shows up. I'm using Win XP Pro.

Anyone else experience this?

Caused by a bug in the recent Q824145 patch.
Microsoft probably knows about it by now.
By the time we get used to this 'new'
feature Microsoft will fix it!!
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Maybe this is the way scrollbar is 'supposed' to work:

Position cursor 'close' to the top/bottom of the
slider and it will scroll one window. Farther away
from slider and it will scroll farther.

Use the mouse wheel to scroll.
See mouse properties to adjust wheel.

Press/Hold/Slide actual bar.

Use keyboard shortcut keys:
Up/Down Arrows (See mouse properties to adjust)
Pageup/Pagedown (This is what you want?)
Home/End (Top/Bottom)

Right-click scrollbar...
Menu pops up...
Select option ("Scroll here" is neat!)
========this MIGHT help=============
"Try" turn off smooth scroll...
Control Panel
-System
--Advanced
---Performance [Settings] button
----Visual effects tab
-----List...
[x] Smooth-scroll list boxes
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