Often I visit pages that are too wide for my screen, forcing me to scroll over to see the right side. What causes this, and how can I avoid it?

Its a Head scratcher Catty

As it happens online it cannot be Desktop settings . I had a peek in Internet Explorer settings Drew a Blank there too
I'm guessing its either Java or Shockwave related if (the Problem) it happens on Pages with text not on a Plain Background

I don't think its your Graphics Card driver

If it was My computer playing these tricks then My first stop would be to Reload the DirectX driver This handles the Text and some graphics and other items
http://en.wikipedia.org/wiki/DirectX

Be aware the download File is Large @ 103 MB Have you a Download manager program? Leechget is simple to use.(download of 3mb) Saves it to a separate file ,then releases it when Full.Can stop your computer and Continue when you return Can also work while its downloading in the Background
http://filehippo.com/download_directx/
will overwrite the old Program

Websites can be written to:

Optimize Screen Resolution and Page Layout
Many sites are set for 1024x768. If your screen is set to 800 X 600 you may be having to use the slider bar to scroll over to see the whole page.
Change you screen resolution in the Display applet in the Control Panel.

Since many monitors being sold today are much larger, page optimization will likely grow. You can also buy a mouse that has a zoom button if you need it sometimes to read page text.

Screen Resolution and Page Layout

Thank you very much, bedstor and Dwight. I believe these aids will take care of the problem.