Mario Party 4

Archeologuess: Beat Shy Guy in story mode
Bowser Bop: Beat Toad in story mode
Extra story mode mini-games: Beat Goomba in story mode
Final Battle: Beat Bowser in story mode
Kareening Koopas: Beat Koopa in story mode
Mystic Match 'Em: Beat Boo in story mode

Unlock Beach Volleyball, Goomba Stomp and Panel Panic mini-games:
Finish the solo mode with any character

Unlock free mode in Beach Volleyball
Finish the battle mode in Beach Volleyball.

Unlock expert difficulty setting
Finish the story mode in easy, medium, and hard modes.

Unlockable objects:
Beat the indicated characters in story mode with the indicated hero
to unlock various objects:

Bowser Lamp: Beat Bowser with Yoshi.
Bowser Object: Beat Bowser with Donkey Kong.
Bowser Picture: Beat Bowser with Peach.
Bowser Television: Beat Bowser with Luigi.
Bowser Vase: Beat Bowser with Mario.
Bowser's Teapot: Beat Bowser with Daisy.
Daisy Doll: Beat Koopa with Daisy.
Daisy's Bed: Beat Toad with Daisy.
Daisy's Flowers: Beat Goomba with Daisy.
Daisy's Nightstand: Beat Boo with Daisy.
Daisy's Table: Beat Shy Guy with Daisy.
Donkey Kong Doll: Beat Koopa with Donkey Kong.
Donkey Kong's Barrel: Beat Toad with Donkey Kong.
Donkey Kong's Box: Beat Boo with Donkey Kong.
Donkey Kong's Stand: Beat Shy Guy with Donkey Kong.
Donkey Kong's Tree: Beat Goomba with Donkey Kong.
Luigi Doll: Beat Koopa with Luigi.
Luigi's Airbike: Beat Goomba with Luigi.
Luigi's Chair: Beat Boo with Luigi.
Luigi's Dumbbell: Beat Shy Guy with Luigi.
Luigi's Table: Beat Toad with Luigi.
Mario Doll: Beat Koopa with Mario.
Mario's Refrigerator: Beat Boo with Mario.
Mario's Sofa: Beat Toad with Mario.
Mario's Table: Beat Shy Guy with Mario.
Mario's Television: Beat Goomba with Mario.
Peach Doll: Beat Koopa with Peach.
Peach's Chair: Beat Toad with Peach.
Peach's Clock: Beat Shy Guy with Peach.
Peach's Table: Beat Goomba with Peach.
Peach's Treasure Chest: Beat Boo with Peach.
Waluigi Doll: Beat Koopa Troopa with Waluigi.
Waluigi's Calendar: Beat Toad with Waluigi.
Waluigi's Chair: Beat Boo with Waluigi.
Yoshi Doll: Beat Koopa with Yoshi.
Yoshi's Computer: Beat Goomba with Yoshi.
Yoshi's Egg: Beat Toad with Yoshi.
Yoshi's Shoes: Beat Boo with Yoshi.
Yoshi's Table: Beat Shy Guy with Yoshi.

Birthday Cake
Beat Beach Volley Folley in tournament mode.

Boo Plate
Dive for 7 or more seconds in the Take A Breather mini-game.

Boo's Photo Stand
Complete the Mario Speedwagons mini-game in maximum 10 seconds.

Goomba Clock
Knock over at least 100 dominos in the Domination mini-game.

Goomba Plate
Finish 15 or more pages in the Bookworm mini-game.

Koopa Plate
Finish the Right Oar Left mini-game within maximum 0:45 seconds.

Shy Guy Plate
Finish the Dungeon Duos mini-game within maximum 1:30 minutes.

Toad Plate
Solve a 40 piece puzzle in Jigsaw Jitters within maximum 3:00 minutes.

Toad Teapot
Solve a 30 piece puzzle in Jigsaw Jitters within maximum 2:00 minutes.

Toad's Cup
Solve a 20 piece puzzle in Jigsaw Jitters within maximum 1:00 minutes.

Bowser Plate:
Complete the Mario Medley mini-game within maximum 1:00 minutes.