I want to know how to roll up the countries of Earth, because I've seen descriptions for a few countries. :lalala

Look for Tomio Hoshino on the select meadow. He gives you the "save earth" level where you roll up all the countries before a meteor hits. You need to do it twice to get both types of meteor's. It's not available until after you complete the Roll up the Cousins level that Mutsuo gives you. Hope this helps. :)

Actually, I think there are three different types of meteors.

You are correct.

Meteor
Mushroom Meteor
Spiky Meteor