DeskJockey
I would steer clear of the PPA. Use the suggested site from Gremlinzzz. PPAs should be used sparingly.
OpenJDK is an open source impementation of Java. It would be nice if the world recognized it as Java, but not everyone does. Some applications and sites require Sun Java.
What you are using on a website is a browser plugin. In the case of OpenJDK it is called IcedTea. Often it simply does not work -- again because it it is not Sun's plugin.
The site referred to by Gremlinzzz says not to remove OpenJDK because doing so might damage your system by removing common dependencies (but I think that has been largely resolved in the most recent versions/repos). This was a beef I had with that site for quite some time (because the instructions used to say to uninstall OpenJDK) until I had contact with one of the maintainers, who assured me that part had been removed.
Use the easy linux tips tutorial. If you can cut and paste, you can do it without "command line skills". Just remember that to paste in the teeminal you need to use CNTL + SHIFT + V.
I install Java by essentially the same process, changing a few things to my purposes and changing the location of the symbolic link to the browser plug in.
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