@garlam Thanks for the reply. Just today, I remembered I was learning Kanji back in my past. And, also today, my wife helped me choose a meaning.

剛 (sturdy)

Reference from http://www.kanjizone.com/kanjiname.aspx?name=Takeshi

As for the meaning... I vaguely remember my Japanese teacher said, Takeshi means "strong".

A reference site says "military, martial": http://www.behindthename.com/name/takeshi

I decided to use "剛 (sturdy)" today. Bing translator gives the meanings as "Tsuyoshi, Takeshi, rigid, goji, gou, gang, Tuyoshi".

Thanks for your help! :)