I would have to say full page ads. Or, if you're really ambitious the best way to monetize your blog is to gather a list of leads that you can then email with related offers from all the networks you are signed up with. You have to get freebie seekers to opt-in and bs them really well into completing the offers. But if you're just starting out, you should just use banners and full page ads. It will work well for you as long as you've got the traffic.