What, like this?
"キングダム ハーツ"
Or are you looking for the names of characters in the game?
バレリー
You may write it as: 中心
植物。It means "plants" in Japanese.
家族
職人
レア Rea
ガブリエル (Gaburieru)
ジェームス(zyeemusu)
The only surefire way to remember the Japanese characters is to write them, write them, write them. It's how the Japanese do it. Fill notebooks, use flashcards, and constantly refresh yourself on what you've just learned. Try ten characters a day!
盆栽
To write in Japanese, you will need to install a Japanese IME on your computer.
The hiragana (basic Japanese characters) is とも, and the most-common kanji (characters originating from China) is 友.