Type in all cheats at the SPECIALS menu:

 ARACHNID             All levels, video sequences and galery pics
 IMIARMAS             Choose level
 ROMITAS              Pause game and choose NEXT LEVEL for level skip
 HEADEXPLODY          Bonus Training Level
 ORGANICWEBBING       Unlimited nets
 KOALA                Fight control
 DODGETHIS            Attacks Matrix style
 JOELSPEANUTS         Enemies have big heads
 UNDERTHEMASK         Ego view
 CHILLOUT             Super cooling

 Player

 GIRLNEXTDOOR         Mary Jane
 HERMANSCHULTZ        The Shocker
 SERUM                Scientist
 REALHERO             Policeman
 CAPTAINSTACEY        Helicopter pilot
 KNUCKLES             Gangster Type 1
 STICKYRICE           Gangster Type 2
 THUGSRUS             Gangster Type 3

 Spider-Man

 FREAKOUT             Matrix
 SPIDERBYTE           Small
 GOESTOYOURHEAD       Big head and feet