First thing would be to reinstall (or try it),
So removing the J2SE Runtime Environment 5.0 Update 6 and J2SE Runtime Environment 5.0 Update 7 would be your first suggestion? Then reinstall?
second would be to downgrade to an older version
Just remove J2SE Runtime Environment 5.0 Update 7?
Failing that...look at upgrading windows?
I have 7 computers. 4 with Win98SE, 1 XP Home , 1 XP Pro and 1 Vista.
I have these variety of systems because I have phone support, I can boot one of the systems up and navigate with the user , makes it easy on me and them

So upgrading is not an option for this particular pc.