"..." indicates spoken parts

Ouji: "Aa dame da dame da yo boku no jinsei tte
  Aa dame da dame da yo boku no seishun tte
  mattaku wakaranai mattaku wakaranai n da
  jinsei tte nannan da ai tte nannan da"
        Prince: "Ah- it's no use. It's just no use about my life.
          Ah- no use. It's just no use about my youth.
          I just don't get it! I just don't understand!
          What is life?! What is love?!"

dou yattara shiawase ni aa nareru n da
        How can I- ah- find happiness?

Ouji: "Shiawase o hitori jime shitai!
  douyattara, dou yattara ii n da!"
        Prince: "I want to gain happiness!
          How should- How should I do it?"

Tennou: "hahaha dame da yo Ouji
  Ouji wa Ouji nan dakara iroiro kangaenakya"
        Tennou: "hahaha it's no use Prince.
          A prince is but a prince so no he has much he has to think about"

Udo: "sousousou sou da yo Ouji
  nayamu koto wa ii koto desu
  ooi ni nayande kudasai. rakushicha ikemasen yo!"
        Udo; "yes yes yes, he's right Prince.
          Worry is a good thing!
          Worry 'big' please, you can't laze about!"

Tennou: "Hai!"
        Tennou: "right!"

Ganbare Ouji! furefure Ouji!
Ganbare Ouji! furefure Ouji!
        Go for it Prince! Wavering Prince!
        Go for it Prince! Wavering Prince!

Tennou: "Ganbatte!"
        Tennou: "Good luck!"

Ouji: "Sonna koto iwaretatte...
  wakaranai n da mon
  yoshi! koko wa hitotsu kossori
  iron na hito ni kiitemiyou! usshisshi"
        Prince: "When you say it like that...
          I can't think of anything!
          Okay! Just once here, secretly,
          I'll go and ask all sorts of people. heheheh"

Nee nee dou yattara shiawase ni nareru no?
        Hey Hey What can I do to find happiness?

Machi no hito A: "un un un
  kantan sa na~nnimo shinakya ii n da yo
  sabocchae! sabocchae!"
        Townperson A: "uh-huh uh-huh uh-huh
          It's easy! Not doing any-thing is best.
          Relax! Relax!"

Ouji: "un un un un"
        Prince: "Uh-huh uh-huh uh-huh"

Machi no hito B: "Sou sa soshite kashino de gyanburu!
  ippatsu atareba
  chou okane mochi saiko jyan!"
        Townperson B: "Right, and gamble at casinos!
          If you win just once-
          become super-rich! Isn't it great!"

Ouji: "sou ka sou ka"
        Prince: "That's so? That's so?"

Machi no hito C: "Chigau yo sou nan jya ikenai
  majime ni kotsukotsu jimichi ni yaru n da yo"
        Townperson C: "Wrong! You can't do it that way!
          Seriously following the rugged honest path is the way!"

Ouji: "e~ mendokusasou"
        Prince: "Aw- what a pain!"

Machi no hito C: "Saa Ouji dore o erabu?"
        Townperson C: "So Prince, which will you chose?"

Docchi da docchi da do~cchi da!
        Which? Which? Whi-ch!

Ouji: "Sonna no kantan jyan
  nanni mo sezu ni gyanburu de ippatsu atatete
  rakushite Shingo Mama o shiawase ni suru n da!"
        Prince: "It's simple isn't it?
          Do nothing, win it big gambling,
          relax and be happy with Shingo Mama!"

Shiawase ni narou! isshou ni
Shiawase ni narou! Shingo Mama! Hai
        Become happy! Together
        Become happy! Shingo Mama! Yeah!

Shingo Mama: "Ouji Watashi ga shitteiru Ouji wa
  sonna hito janakatta kirai"
        Shingo Mama: "Prince, the Prince I knew was not that sort of person.
          I hate you"

Shingo Mama: (sings) Ouji Ouji Ouji kirai yo
        Shingo Mama: (sings) Prince Prince Prince I hate you

Ouji: "Doushite? rakushite shiawase ni nareru n da yo"
        Prince: "Why? We can be happy if we just relax!"

Shingo Mama: "Zannen ne wakatte moraenai you da wa
  sayounara"
        Shingo Mama: "Too bad, looks like you won't understand.
          Good-bye"

Ouji: "Ee! Matte yo nee matte yo!"
        Prince: "Huh? Wait! Hey, Wait!"

doushite nan da? naze da?
nani ga ikenai to iu no ka?
        How can it be? Why?
        What do they say can't be done?

Ouji: "Doushite nan da!"
        Prince: "How can it be!"

Chonan: "Yoboseyo uenniriya? hahaha
  uanja
  Ouji wa taisetsu na koto o wasureteimasu.
  beryohanun maumu omoiyari no kokoro desu"
        Chonan; (half in Korean) Yoboseyo uenniriya? hahaha
          uanja
          Prince is forgotting a very important thing.
          beryohanun maumu A considerate heart"

Ouji: "Omoiyari no kokoro?"
        Prince: "A considerate heart?"

Chonan: (sings) Jibun no koto dake o kangaenaide
  aite no kimochi ni natte ne uanja
  sekaijuu na Ouji no yasashisa o kidarigo itta!
        Chonan: (sings) Don't just think of only yourself.
          Think of the other person's feelings.
          In all the world the Prince's kindness is kidarigo itta!

Ouji; "un!"
        Prince: "yes!"

Chonan: (korean) "cha! igosurusojo!"

Ouji: "Arigatou! sou ka
  Omoiyari no kokoro o wasureteita n da ne, yoshi"
        Prince: "Thank you" I see,
          I forgot about a considerate heart. Okay!"

Daremo ga moteru sa omoiyari no kokoro
boku ni mo dekiru sa omoiyari no kokoro
sekaijuu ni omoiyari no hana o sakaseyou
        Anyone is carrying one- a considerate heart
        Even I can do it- a considerate heart
        All over the world let's bloom flowers of consideration

Shingo Mama: "yatto wakattekureta no ne ureshii wa!"
        Shingo Mama: "You finally understood! I'm so happy!"

Ouji: "Shingo Mama!"
        Prince: "Shingo Mama!"

Sorezore ni: "Sou da! Sou da! yokatta yokatta
  matteta yo sono kotoba..."
        Various others: "That's right! That's right! Good Good.
          I've waited for those words!"

Ouji: "Minna arigatou ganbaru yo utaou!"
        Prince: "Thank you everyone. Let's do our best! Sing!"

Ouji: (sings) Sekaijuu ni omoiyari no hana o sakaseyou   Sekaijuu ni omoiyari no hana o sakaseyou
        Prince: (sings)All over the world let's bloom flowers of consideration
          All over the world let's bloom flowers of consideration

Sekaijuu ni omoiyari no hana o sakaseyou
Sekaijuu ni omoiyari no hana o sakaseyou
        All over the world let's bloom flowers of consideration
        All over the world let's bloom flowers of consideration

Sekaijuu ni omoiyari no hana o sakaseyou
Sekaijuu ni omoiyari no hana o sakaseyou
        All over the world let's bloom flowers of consideration
        All over the world let's bloom flowers of consideration

Ouji: "Sou ka! Sou datta no ka
  minna mattekureta n da ne kono chikyuu ni
  minna no chikara de omoiyari no hana o sakaseyou yo!
  boku mo zettai ni omoiyari no kokoro o wasurenai
  YEAH! Sakaseyou yo"
        Prince: "That's it! So that was it!
          Everyone waited for me, huh? On this Earth,
          with everyone's power, let's bloom flowers of consideration.
          I'll definitely never forget a considerate heart.
          Yeah! Make them bloom!"

Sekaijuu ni omoiyari no hana o sakaseyou
Sekaijuu ni omoiyari no hana o sakaseyou
        All over the world let's bloom flowers of consideration
        All over the world let's bloom flowers of consideration

Notes;
Regarding Chonan's parts, I don't understand Korean, I just romanized what was written in katakana. A Korean classmate of mine told me he's basically just repeating himself in both languages, so there's theoretically nothing lost in translation