Channel 1 is the weather channel, and it will tell you the current day's channel. It is an especially important channel if you have animals, because you need to know the weather and if you can take your animals out yourself. If it is raining, you also need to make sure that they are inside.
This is the news channel. It will tell you about upcoming events and festivals.
This is the tutorial channel. You can go here to find out about how to use any tools and other basic things like that. It will also give you information and tips on how to raise your animals.
This is the variety show channel, though this channel was removed in non-Japanese versions of the game and replaced with static. The dialogue is quite lengthy and it is speculated it may have been removed as the translations would have taken up a considerable amount of space on the cartridge and not contributed much, if anything, to the game.