After R.D.Burman, The only Music Director to fill in his shoes is A.R.Rehman. His First Hindi Movie - Rangeela (Sorry..Roja and Humse hai mukabla were dubbed films) Shot him to nothing less then Super Stardom in the Hindi Film World. The First Music Director to command and get Rs 10 Million per film. I wont get to any more of his personal details as this review is supposed to be on the top 10 songs of A.R.Rehman.
I will limit myself to Hindi Film Songs of A.R.Rehman as I have not heard much of A.R.Rehman’s Music Work of Regional Films.

1)Chaiiya Chaiiya
Film - Dil Se
Lyrics - Gulzar
Singers - Sapna Awasthi & Sukhwinder Singh

2) Ruth Aa Gayi Re
   Film - 1947 - Earth
   Lyrics - Javed Akhtar
   Singers - Sukhwinder Singh

3) Yeh Jo Chali Hawa
   Film - 1947 Earth
   Lyrics - Javed Akhtar
   Singers - Hariharan

4) Mil Gayi Woh Manziley
   Film - Kabhi Na Kabhi
   Lyrics - Javed Akhtar
   Singers - Alka yagnik & Kumar Sanu

5) Khamosh Raat
   Film - Thakshak
   Lyrics - Mehboob
   Singers - Roopkumar Rathod

6) Toofan Ki Raat
    Film - Thakshak
    Lyrics -Mehboob
    Singers - Alisha Chinoy

7) Chale Chalo
   Film - Lagaan
   Lyrics - Javed Akhtar
   Singers - A.R.Rehman

8) Pagdi Sambhal
   Film - The Legend Of Bhagat Singh
   Lyrics - (I Do not know who wrote the lyrics to this song)
   Singers - Sukhwinder Singh

9) Shabba Shabba
   Film - Daud
   Lyrics - P.K.Mishra
   Singers - S.P.Balasubramaninam & Neeraj Vohra

10) Sarfaroshi Ki Tamanna
    Film - The Legend Of bhagat Singh
    Lyrics - Ram Prasad bismil
    Singers - Sonu Nigam & Hariharan

The Above Songs are in no particular order. They are just the 10 best A.R.Rehman Directed Songs according to me and I am sure that many may or may not agree with me. But Then everybody has an opinion.

Let Me also mention a few films where A.R.Rehman has given superb background Score
Iruvar(Tamil), Indian(Tamil), Roja(Tamil), Lagaan(Hindi), 1947 Earth (Hindi), Daud(Hindi), Thakshak(Hindi), The legend OF Bhagat Singh(Hindi), Rangeela(Hindi) & Taal(Hindi)