The Japanese of "thank you" is Arigato Gozaimas/Arigato/Arigato Gozaimasu
The Japanese of "thank you very much" is Domo Arigato Gozaimas/Domo Arigato/Domo Arigato Gozaimasu...
(note: If you want to use a Japanese language in a sentence, use desu to make it more generous =] hehe! )
有り難う 有難う is commonly used as the kanji, but it is technically wrong. Most people will write this in hiragana only.
We write it as 鯉[koi] in kanji in Japanese.
There is no Kanji for "madsam."
you can't
Earthquake in kanji is written as 地震.
龍 or 竜
'Ojiichan' written with kanji isお祖父ちゃん.
you don't its written in katagana
櫻.
you don't its written in katagana
酒 is the Kanji for sake.
尊厳 Songen