can’t access plugins

I installed a bunch of plugins and activated most of them. One of them would not activate because of a flaw in the code or something so I went back to the previous page to look at the rest of the plugins and all i get is a page that says Manage Plugins and nothing on the page. I also noticed that when I go to the widget page it shows all my widgets but no columns showing to drag them into. Do I have to reinstall the theme or is there a way to fix the problem?