In reply to mack:
It is safe to remove Java and reinstall it. Programs which rely on it won't work while it is missing, but your computer will start up just fine.
Go into "add or remove programs" (on Windows 7 just type that into the box in the start menu and click it when it shows up). You'll probably find many many versions of java in the list, remove all of them. This should get rid of Java, but because it's badly written, it will leave some leftovers, hopefully they won't matter though.
Then download and install Java, a fresh download from the java website is probably a good idea. Make sure you untick the box to install the free browser toolbars if it comes up.
If that doesn't work, you could try again but removing all the leftovers. Post up and someone will tell you how.
It's also possible that those programs won't work with new versions of Java, this update removes Java 6 support. What programs are affected?