As you know by now, Apple, LW and others have given up on Java for OS 9 already.

A crash caused by clicking on the About Box (or any Menu) used to indicate an Extensions conflict: disabling FaxStF extensions was one solution. Try running with a minimum set of extensions.

Otherwise, just avoid that menu. Switching to OS X is really the solution.

What program/OS is your friend running? Maybe your friend could email you a magnet of the file you want. Otherwise you should be able to find each other's files by sharing a unique file and searching for it.