It is FM ver 10 by the way.
What Operating System?
I have Filemaker 10v3 advanced, Windows XP. I just clicked through 40+ records on a layout with a web viewer and Things would slow down, but I didn't experience a crash. You might want to do a few tests.
Create a new layout and test.
Try with a different file.
Check to see if a Specific URL assigned to the viewer triggers the crash.
Recover the file and test the recovered copy to see if it behaves the same.