Can I set my forum to a max 1024 pixels ?

[netsniper]

Can anyone tell me if its possible to change my forum settings so that its at a max of 1024 pixels, as I am getting members saying that they can not see all the forum ? below is a message I received today and I have got 3 others too, what the problem seems to be is that they have to scroll horizontally to see the rest of the forum, I have done all I can here and they have checked their settings, but this has only started today? so is it yet another problem from IBM?

The screen is now to big to read all the thread and have to keep going back and forwards very hard to follow a thread also some new members are voicing the same on another forum don't want to lose them as members any help with this problem would be great thanks ****

Thank you