Do the other computers also have Filemaker 7 installed or might they have filemaker 10?
If they all have the same version installed and this file works correctly with all but one computer, I'd re-install the software on that one computer and see if that fixes things.
Can you enter a field, and highlite the contents or copy and paste the contents into a text editor?
I ask simply because I have seen similar issues, the layouts look a mess, field contents can only be seen in preview mode etc, however I described my problem more in terms of graphics missing in FM9 & 10... but on some systems the field contents appeared blank also.
Also try going to your display properties and turning hardware accelleration down, see if that has any effect.
It may be related... it may not, but some of the effects sound similar.
The culprit turned out to be a recently installed version of Quicktime. For some reason, the version just installed affected the display fonts in FileMaker Pro 7...I kid you not. We tried uninstalling and reinstalling FMPro 7, and several other cycles, but it was uninstalling Quicktime that solved the problem!