Avast! Browser Cleanup is a free portable tool which can list the addons for IE, Firefox and Chrome, highlight any it thinks are particularly poor, and allow you to disable or remove them.
Launch the program and it will check your addons for any which "have a poor reputation" (according to their users), or "engage in aggressive tactics" to manipulate your settings. If any are discovered then these will be displayed on an Summary screen, and you can remove them all with a click.
After that, you can click a browser tab to display any associated addons, along with their user ratings. You can obviously do this from within the browser itself, but avast! Browser Cleanup does by default exclude addons with a good rating from the list, which might make it easier to spot the more dubious extensions.
If you decide a particular addon is surplus to requirements then clicking "Disable" will disable it completely (there's no "Remove" option here, unfortunately).
And there's also a "Reset browser settings to default" option which will restore your home and search pages to their default value. The product's home page has more.