Go to the Options Screen and then to Code Input.  Then, type in GMMSKIN as a code.

Full Rage Meter

Go to the Options Screen and then to Code Input.  Then, type in ANGMNGT as a code.

Regenerator

Go to the Options Screen and then to Code Input.  Then, type in FLSHWND as a code.

Unlimited Continues

Go to the Options Screen and then to Code Input.  Then, type in GRNCHTR as a code.

Puzzle Solved

Go to the Options Screen and then to Code Input.  Then, type in BRCESTN as a code.

Wicked Punch

Go to the Options Screen and then to Code Input.  Then, type in FSTOFRY as a code.

Double HP for Hulk

Go to the Options Screen and then to Code Input.  Then, type in HLTHDSE as a code.