So much wrong info in so few posts...

For use with Bootcamp, You will need a shrinkwrapped (i.e. a full CD) version of Windows XP SP2 or later, Win Vista SP1 or later or Win 7. Both 32 and 64 bit versions of Win Vista and Win 7 works fine. You will need to have a single partition Mac, go to the Utilities folder and launch BootCamp Assistant and it will walk you through setting up BootCamp. On the first page is asks you to print out a PDF, this PDF has an exact step by step walkthrough with pictures, so should be very easy to follow.
Note you will need to boot into Windows, so you can't have both running at the same time. For that you will need Parallels or Fusion instead.

As for the java thing, launch Java Preferences from the Utilities folder and in the general tab it will list 2 different versions of Java, try to move one on top of the other relaunch your browser and it will then try and launch the java applets with the other version of Java installed. This solves most Java problems.

As for your other 2 problems, yes then you will most likely need to be booted into Windows or Paralles/Fusion for them to work.