Java-based windows display and response error

I have just installed the 1.4.2 SDK, and are having problems viewing and using any java based program and any java applet. An example would be the JEdit installer, upon startup there is no text presented and will only display if a certain part of the window is clicked by accident. At which the window will maximise and display all, but causes the windows taskbar to turn black, as well as the background. After installation the problem cant be used as menu are unresponsive.

Java applets aren't displayed at all, leaving an image of the previous window and a white void on the screen. I have installed a java sdk before, and I never had such problems, could it be a problem with me having upgraded up XP? What can I do to fix this problem?

Thanks in advance.

[779 byte] By [s2noxa] at [2007-10-1 2:32:05]
# 1
If java applets aren't displayed at all, you probably don't have a java enabled browser. Or are you using appplet viewer?
james91a at 2007-7-8 11:39:51 > top of Java-index,Administration Tools,Sun Connection...
# 2
Go here http://java.com/en/download/help/testvm.jsp and if you have problems follow the directions.
ChuckBinga at 2007-7-8 11:39:51 > top of Java-index,Administration Tools,Sun Connection...