Animal Crossing: Wild World features a very minimal plot. The objective of the game is to pay off a debt to Tom Nook, who allows the player to move into a house he owns. If the mortgage is paid off, the player's house will expand until upstairs, left, right, center and back rooms are included. This is slightly different to the Nintendo GameCube version, in which the finished house only consisted of a basement, a main room and an attic. While paying off a debt, the player can do a variety of optional tasks, including interacting with other villagers and filling the catalog of the things you have, like furniture, fish, clothes. 

Animal Crossing: Wild World makes use of several of Nintendo DS' features, including the touch screen, dual screens and internal clock. The touch screen is used for menu navigation and interacting with the surrounding area, including movement, using tools, talking to other villagers, entering buildings, picking up items etc. The dual screens are used to display the overworld on the touch screen and the sky on the top screen, which varies depending on the circumstances. 

HINTS

CHARACTERS

Mr. Resetti: Home
In the Japanese version of the game, restart the game at least two times to have Mr. Resetti appear. Next, use a shovel to hit all the rocks until one cracks. Hit that rock again then enter the hole that appears to find Mr. Resetti's home.

Mr. Resseti: Make him pop up on opposite side
When Mr. Ressetti is about to pop up, run to the side of the door that does not have the mail box. Mr. Resseti should be on the opposite side.

Pascal: Determining when he will appear
Talk to a sea animal such as Marina (the squid that calls you blurp). Sometimes they will say something similar to "Today is Thursday, the best day to collect shells!". You can tell if they are a sea animal if they walk near the beach frequently. In this example, Pascal will probably appear on Thursday.

Here's a video of this popular game: