Java is a programming language.
What you have a partially broken installation of that you can't fix is the RTE - runtime environment, the gubbins needed so that you can run programs written in Java on your computer.
(If you don't want to run any programs written in Java then you don't care whether you've got an Java RTEs installed or how many of them are broken.)
Now, whilst Java is sold as "write once, run anywhere" the truth of the matter, as someone who gets paid to write the stuff, is rather different.
Quite apart from the fact that software that works on one type of platform quite likely won't work on another is that every version of the RTE, even on the same computer, has different sets of bugs.
So you can have program A working perfectly happily; you install program B, which installs a different version of the Java RTE; and program A stops working.
Basically you're in nightmare territory. When I get Java installations getting their knickers in a twist I uninstall them all using the control panel, then delete the remains manually, then if I can be bothered I run a registry cleaner, then I find out which applications don't work any more and pick a version of Java at random to re-install. Or something. Like I said, nightmare.