Pause the game and press Up(2), Down(2), Left, Right, Left, Right, X, Square, Triangle, Circle. 

Gameshark codes

Infinite Health Area 7-1, 7-4 801578cc012c
Infinite Spirit Area 7-1, 7-4 801578d0012c
Infinite Money Area 7-1, 7-4 801578dc270f
Infinite Health Area 7-3 80128adc012c
Infinite Spirit Area 7-3 80128ae0012c
Infinite Money Area 7-3 80128aec270f
No Health Boss Area 7-3 80128f5c0000
No Spirit Boss Area 7-3 80128f600000
Infinite Health (Restore World) 801484e4012c
Infinite Spirit (Restore World) 801484e8012c
Infinite Money (Restore World) 801484f4270f
No Health Boss (Restore World) 801489640000
No Spirit Boss (Restore World) 801489680000
No Health Boss Area 6-3 80144b440000
No Spirit Boss Area 6-3 80144b480000
Infinite Health Area 6-4 8012ab5c012c
Infinite Spirit Area 6-4 8012ab60012c
Infinite Money Area 6-4 8012ab6c270f
No Health Boss Area 6-4 8012afdc0000
No Spirit Boss Area 6-4 8012afe00000
Stop Time Before Core Blows Area 6-4 80128aa01c2f
No Health Boss Area 7-1 8015814c0000
No Spirit Boss Area 7-1 801581500000
No Health Boss Area 7-4 80157f4c0000
No Spirit Boss Area 7-4 80157f500000
Infinite Spirit Area 5-2b 8012c878012c
Infinite Money Area 5-2b 8012c884270f
No Health Boss Area 5-2b 8012ccf40000
No Spirit Boss Area 5-2b 8012ccf80000
Infinite Health Area 5-3 8011c12c012c
Infinite Spirit Area 5-3 8011c130012c
Infinite Money Area 5-3 8011c13c270f
No Health Boss Area 5-3 8011c5ac0000
No Spirit Boss Area 5-3 8011c5b00000
Infinite Health Area 6-2 8013807c012c
Infinite Spirit Area 6-2 80138080012c
Infinite Money Area 6-2 8013808c270f
Infinite Health Area 6-3 801446c4012c
Infinite Spirit Area 6-3 801446c8012c
Infinite Money Area 6-3 801446d4270f
Infinite Money Area 4-3 8012a75c270f
No Health Boss Area 4-3 8012abcc0000
No Spirit Boss Area 4-3 8012abd00000
Infinite Health Area 4-4 80125674012c
Infinite Spirit Area 4-4 80125678012c
Infinite Money Area 4-4 80125684270f
No Health Boss Area 4-4 80125af40000
No Spirit Boss area 4-4 80125af80000
Area 5-2A
Infinite Health Area 5-2a 8012623c012c
Infinite Spirit Area 5-2a 80126240012c
Infinite Money Area 5-2a 8012624c270f
No Health Spider Mini-Boss Area 5-2a 801271bc0000
No Health Boss Area 5-2a 801266bc0000
Infinite Health Area 5-2b 8012c874012c
Infinite Money Area 3-5 8012f584270f
No Health Boss Area 3-5 8012fbf40000
No Spirit Boss Area 3-5 8012fbf80000
Infinite Health Area 4-1 801324e4012c
Infinite Spirit Area 4-1 801324e8012c
Infinite Money Area 4-1 801324f4270f
No Health Boss Area 4-1 801329640000
No Spirit Boss Area 4-1 801329680000
Infinite Health Area 4-2 8011dfdc012c
Infinite Spirit Area 4-2 8011dff0012c
Infinite Money Area 4-2 8011dffc270f
No Health Boss Area 4-2 8011e45c0000
No Spirit Boss Area 4-2 8011e4600000
Infinite Health Area 4-3 8012a74c012c
Infinite Spirit Area 4-3 8012a750012c
Infinite Health Area 3-2 801277fc012c
Infinite Spirit Area 3-2 80127800012c
Infinite Money Area 3-2 8012780c270f
Infinite Health Area3-3 8013033c012c
Infinite Spirit Area 3-3 80130340012c
Infinite Money Area 3-3 8013034c270f
No Health Boss Area 3 801308bc0000
No Spirit Boss Area 3 801308c00000
Infinite Health Area 3-4 8013a1ec012c
Infinite Spirit Area 3-4 8013a1f0012c
Infinite Money Area 3-4 8013a1fc270f
No Health Boss Area 3-4 8013a76c0000
No Spirit Boss Area 3-4 8013a7700000
Infinite Health Area 3-5 8012f574012c
Infinite Spirit Area 3-5 8012f578012c
Infinite Spirit Area 1-3 80136f20012c
Infinite Money Area 1-3 80136f2c270f
No Health Boss Area 1 8013749c0000
No Spirit Boss Area 1 801374a00000
Infinite Health Area 2-1 8014f514012c
Infinite Spirit Area 2-1 8014f518012c
Infinite Money Area 2-1 8014f524270f
Infinite Health Area 2-2 8015466c012c
Infinite Spirit Area 2-2 80154670012c
Infinite Money Area 2-2 8015467c270f
No Health Boss Area 2 80154bec0000
No Spirit Boss Area 2 80154bf00000
Infinite Health Area 3-1 801325d4012c
Infinite Spirit Area 3-1 801325d8012c
Infinite Money Area 3-1 801325e4270f
All Options & Secret Mode Enabled 8001002affff
Infinite Credits 3001006f0009
All Options Enabled 3001007300ff
Infinite Health Area 1-1 8013fd94012c
Infinite Spirit Area 1-1 8013fd98012c
Infinite Money Area 1-1 8013fda4270f
Infinite Health Area 1-2 8013bfac012c
Infinite Spirit Area 1-2 8013bfb0012c
Infinite Money Area 1-2 8013bfbc270f
Infinite Health Area 1-3 80136f1c012c