Personally, I'd go with html first. That's pretty much the base for doing anything else online. Knowing that would make it easier down the road for you to add in anything you did with java if you choose to learn that later. Are you planning to take a course or just get a book? I've found the "HTML For Dummies" book to be pretty good if you're looking to use a book. Whatever you decide to do, have fun.
Ann