yep, you're right, it's usually to do with large width images, or quotes inside quotes etc.
Basically, anything that won't word wrap in the text area.
Images onviously can't break into another line, and quote always have a set pixel indent width.
It's not a problem of the forum really.
You could always try increasing your screen resolution, that would give you more screen area and you would have more width to play with.
i run at 1152 x 864 and rarely come across a thread that does this.
To change your resolution:
Google search results (check this lot first, probablly one in more detail there)
or (quick version, in XP this is, same on 98 etc though)
Right click on the windows background
"properties"
"settings" tab
Move the slider up around 1024 or higher (you'll have to play with this to see what resolution your monitor supports)
then "ok"
becareful when you select a higher resolution than your monitor can take, you monitor will cut out and go black... if so, then just leave it for 15 seconds and it should return back to you previous setting.
Also, if you set you new resolution and you find the new mode a bit "flickery", it's because the new monitor refresh rate has been lowered (usually down to 60hz)
go back into the same area, but then into the "advanced" area, then change the "refresh rate" to as high as your monitor can take.
Same black out will occur if you set this too hgih... just wait 15 secs and it should return.
If you royally screw that up and it gets set to a mode where your monitor is black all the time. then reboot and enter wndows in "safe mode"
Press F8 at start up, just before the widows logo.
get back in there and reset it.
hope that helps someone.
Cheers
Carlo