Even though I had deactivated the PHP Executable plugin earlier, it seems to be causing me trouble now anyway. The right sidebar widget admin area is missing its Save changes button, and on all my posts and pages, the very bottom is missing, where the copyright is. I've deactivated or deleted plugins that I thought might be causing this, but I'm stumped. Flynn, help? Could it be Any Code?

You are probably have some malformed PHP or html. Look through all you're code snippets to make sure things are balanced. (closing brackets in right place, semi-colons, etc.)

I sometimes find it useful to pull code into Dreamweaver or some code tool that color codes the code. it is helpful. It is tricky with with these dynamic pages as the code from the server comes from sever files and database calls.

Good Luck!