Delete saved data
Push Up, Up, Down, Down, Left, Left, Right, Right in the title screen.

Gallery Corner Museum
You will need 60 Stars to unlock the nine titles for display only (not gameplay). They are, in order of appearance - Manhole, Tropical Fish, Mario's Bombs Away, Parachute, Bombsweeper, Climber, Safebuster, Lifeboat, Zelda.

Five extra games
As you gain more Stars, you can unlock Chef, Mario Bros., Donkey Kong, Octopus, and Fire Attack (in that order) for classic and modern game play.

Star features
The more stars you gain, the more features you will unlock. Note - Museum games are classic play only. You do not earn any Stars for the games in the museum.

5 - Chef
10 - Manhole (View only)
15 - Tropical Fish (View)
20 - Mario Bros.
25 - Mario's Bombs Away (View)
30 - Parachute (View)
35 - Donkey Kong
40 - Bombsweeper (View)
45 - Climber (View)
50 - Octopus
55 - Lifeboat (View)
60 - Zelda (View)
65 - Fire Attack
70 - G&W History (Gallery Corner Feature)
80 - Manhole (Classic Play)
90 - Tropical Fish (Play)
100 - Mario's Bombs Away (Play)
110 - Parachute (Play)
120 - Bombsweeper (Play)
130 - Climber (Play)
140 - Safebuster (Play)
150 - Lifeboat (Play)
160 - Zelda (Play)

More difficult star mode
By getting 1,000 points in modern mode you can unlock the more difficult star mode.