If the normal methods of unlocking the medal options is too hard for you, you can always do it an alternate way. These methods do not gain you the medals, but instead merely unlock the bonuses gained by them.
Bronze: Complete Original Mode with Sakura 8 times
Silver: Complete Original Mode with Vega 8 times
Gold: Complete Original Mode with Ryu 8 times
Platinum: ''vs. Vega II'': Win 4 battles, ''vs. True Vega'': Win 4 battles
Fight as Bison II
Successfully complete the game in original mode as M.Bison eight times without continuing. Highlight M.Bison, then hold Select and press X, Square, or Circle at the character selection screen.
Fight as Evil Ryu
Successfully complete the game in original mode as Ryu eight times without continuing. Highlight Ryu, then hold Select and press X, Square, or Circle at the character selection screen.
Fight as Kairi
Win all matches in original mode with a Meteo Combo, Meteo Tag Combo, or Character Parade as Hokuto or Nanase.
Fight as True Vega
Get all ten platinum medals in original mode. True Vega will be unlocked in arena mode.
Hidden Battles
There are three extra battles available to you in Original Mode, depending on the character you select. Finish every stage with either a Meteo Combo, Meteo Tag Combo, or Character Parade to unlock the respective hidden battle:
vs. Kairi: Hokuto or Nanase
vs. Shadow Geist: Skullomania or Sharon
vs. Evil Ryu: Sagat, Ken, Sakura, and Vega or Vega II
Hidden characters
Complete original mode with a regular character to unlock one of the hidden characters.
Sagat: Beat the Original Mode game once without continues
Vega: Beat the Original Mode game twice without continues
Garuda: Beat the Original Mode game three times without continues
Shadow Geist: Beat the Original Mode game four times without continues
Kairi: Beat the Original Mode game five times without continues
Pullum: Beat the Original Mode game six times without continues
Area: Beat the Original Mode game seven times without continues
Darun: Beat the Original Mode game eight times without continues
Vulcano: Beat the Original Mode game nine times without continues
Hidden characters
Complete original mode with a regular character to unlock one of the hidden characters.
Meteor Tag Teams
Ken/Ryu
Down to left, down to the left, triple punch
Sakura/Ryu
Low punch,low punch, left, low kick, high punch
Nanase/Hokuto
Low punch,low punch, left, low kick, high punch
Pullum/Darun
Down to left,down to the left, triple punch
Zangief/Darun
720 degrees, triple kick
Blanka/Dhalsim
Left (hold for 2 sec) right, left, right, triple punch
V.Russo/Jack
Left (hold for 2 sec) right, left, right, triple punch
Guile/Chun-Li
Left (hold for 2 sec) right, left, right, triple punch
Bison/Vega
Left (hold for 2 sec) right, left, right, triple kick
Narrator Sakura
Successfully complete the game in original mode as Sakura eight times without continuing. Highlight Sakura, then press Select at the character selection screen. Alternately, get all ten bronze medals in original mode.
Rainbow team combo
Press Down, Down/Right, Right four times and press Tag to create a Rainbow Flash team combo. Note: Your partner will not stay in and all the moves you do will be the ones that your friend does.
Ryu's secret move
Press Down, Down/Left, Left (quarter-circle going back), PPP and he will dash back.
Secret Character Finishing Moves
Note: Meteor Combos are finishers and are used only when your meter flashes red.
Kairi
Shouki-Hatsudou
Down to right, Down to right, Triple Punch
Pullum
Gradus Par
Down to right, down to right, Triple Punch
Area
Final Cancer
Down to left, down to left, Triple Punch
Bison
Meteor Combo
Left (Hold for 2 sec) Right, Left, Right, Triple Punch
Shadow Geist
Meteor Combo
Down to left, Down to left, Triple Punch
Sagat
Meteor Combo
Down to right, Down to right, Triple Punch
Garuda
Meteor Combo
Down to left, Down to left, Triple Kick
Skullomania's secret move
Press Low Punch(2), Back, Low Kick, High Punch. Skullomania will do a different Skullo Dream. There is a part with Skullomania and the enemy eating something at a Japanese table.