Cheats:

 Press [Esc] to bring up the exit options screen. Then type 7TH,
 followed by these codes and [Enter]. If Joey says 'Uh, oh', then
 you've entered the code incorrectly. If Joey says 'COOL', then
 you've entered the code correctly.  Click on 'No Way' to return
 to the game.

 ANGEL          One extra live
 MAKEAWISH      Ten extra lives
 ILOVEJOEY      50 extra lives
 GIMMEAMMO      Ten extra bullets
 BLASTEM        100 extra bullets
 GOLDENGUN      500 extra bullets
 OMNIJOEY       Invulnerability
 URHOPELESS     Get special item
 FATBOYCANTJUMP Enable fly mode
 HALEJOEY       Restore full health
 WARP2SINNERS   Warp to Alcatraz
 WARP2SLOTS     Warp to Las Vegas
 WARP2GORGE     Warp to Grand Canyon
 WARP2FACES     Warp to Mt. Rushmore
 WARP2MUDPIT    Warp to Oklahoma
 WARP2GUNFIGHT  Warp to Alamo
 WARP2DOLLS     Warp to Mardi Gras
 WARP2RESORT    Warp to Miami
 WARP2WHOUSE    Warp to Washington D.C.
 WARP2THEAPPLE  Warp to New York
 WARP2WBOGUS    Warp to Woodstock (no goons)
 WARP2WLATE     Warp to Woodstock (too late)
 WARP2WCOOL     Warp to Woodstock (success)
 ROAD2SLOTS     Road to Las Vegas
 ROAD2GORGE     Road to Grand Canyon
 ROAD2FACES     Road to Mt. Rushmore
 ROAD2MUDPIT    Road to Oklahoma
 ROAD2GUNFIGHT  Road to Alamo
 ROAD2DOLLS     Road to Mardi Gras
 ROAD2RESORT    Road to Miami
 ROAD2WHOUSE    Road to Washington D.C.
 ROAD2THEAPPLE  Road to New York
 ROAD2THEGIG    Road to Woodstock
 GIMMETIME      Set location time to 10 min.
 NOSCORE        Set score to 0
 NOTIME         Set location time to 30 sec.
 NOBULLETS      Set bullets to 0
 NOHEALTH       Set health to 1/4
 TOGGLEWIGGLE   Toggle pull item wiggle
 MAVERICK       Toggle shoot down
 IMAGONER       Set to last life, 1/4 health

 Part of the codes taken from Scott's Arcade America Page