Dimming lights is probably caused by voltage dips during peak load times. This is completely different to surges. Surge arrestors won't help protect against voltage dips I'm afraid.

Most decent electronic items have their own built-in surge protection, if you're living in an area that's notorious for lightning strikes then supplimentary surge protection can't hurt but look at protecting the entire installation by having them installed in your DB rather than just protecting individual appliances with a 'piggy-back' type unit at the plug.