Art Gallery pictures:

Complete five puzzles in puzzle mode to unlock one picture in the Art Gallery. Note: Other difficulty settings will unlock other pictures. More pictures are unlocked at various progress points in Wipeout and Marathon modes.
Bronze Marathon trophy:

Survive five minutes in Marathon mode under the easy difficulty setting.
Bronze Puzzle trophy:

Successfully complete Puzzle mode under the easy difficulty setting.
Bronze Wipeout trophy:

Clear all blocks in Wipeout mode under the easy difficulty setting.
Gold Marathon trophy:

Survive five minutes in Marathon mode under the hard difficulty setting, after getting Silver.
Gold Puzzle trophy:

Successfully complete Puzzle mode under the hard difficulty setting, after getting Silver.
Gold Wipeout trophy:

Clear all blocks in Wipeout mode, under the hard difficulty setting, after getting Silver.
Hard Marathon mode:

Survive five minutes in Marathon mode under the medium difficulty setting.
Hard Puzzle mode:

Successfully complete Puzzle mode under the medium difficulty setting.
Hard Wipeout mode:

Clear all blocks in Wipeout mode under the medium difficulty setting.
Silver Marathon trophy:

Survive 5 minutes in Medium Marathon (After getting Bronze)
Silver Puzzle trophy:

Successfully complete Puzzle mode under the medium difficulty setting, after getting Bronze.
Silver Wipeout trophy:

Clear all blocks in Wipeout mode under the medium difficulty setting, after getting Bronze.
Special Marathon mode:

Successfully complete Marathon mode under the hard difficulty setting.
Special Marathon trophy:

Successfully complete Marathon mode under the special difficulty setting, after getting Gold.
Special Puzzle mode:

Successfully complete Puzzle mode under the hard difficulty setting.
Special Puzzle trophy:

Successfully complete Puzzle mode under the special difficulty setting, after getting Gold.
Special Wipeout mode:

Successfully complete Wipeout mode under the hard difficulty setting.
Special Wipeout trophy:

Successfully complete Wipeout mode under the special difficulty setting, after getting Gold.