To switch to the OLD STYLE: On the main LJ page: Top right corner in the blue menu bar, there's an empty square you can click on, between "Post to Blog" and the little magnifying glass search. If you click it you get a popup asking if you want to explore the new features or switch back to old.
Edit: I've got a speech bubble with a question mark in it. Just clicked it; can read and understand LJ again. Phew!
Hope it's helpful all round!
Why oh why can't they just leave things as they are. *sighs*