Difficult to choose just 10 since Bollywood has produced so many, thus, picking top 20. Not in any order:
Sahib Bibi Aur Ghulam
Mughal-E-Azam
Guide
Mera Naam Joker
Chupke Chupke
Abhimaan
Roti Kapda Aur Makaan
Sholay
Gol Maal
Arth
Jaane Bhi Do Yaaro
Prahaar
Nayakan
Parinda
Andaz Apna Apna
Hum Aapke Hai Kaun
Roja
Lagaan
Dil Chahta Hai
The Legend of Bhagat Singh
Hari Bhari
Ankur
Raincoat
Suraj Ka Satwaan Ghoda
Kaun
Darna Mana Hai
Andaz Apna Apna
Hum aap ke hain kaun
Dilwale dulhaniya ley jeaeyngey
Zubaida
Mixed Doubles
Joggers Park
Dil to pagal hai
DEVDAS (old K.L. Sehgal's)
Lagaan
Dil chahta hai
In no Particular order, apart from Andaz Apna Apna being Number 1!!!
Andaz Apna Apna
Masoom (The Shekar Kapoor one)
Raja Hindustani
Sholay
Raja Babu
Deewana Mastana
Mukadar ka Sikandar
Anjaam
Khel
Chalbaaz
In no particular order
Andaz Apna Apna
Kabhi Haan Kabhi Naa
Lagaan
Dil Chahta Hai
Maqbool
Gol Maal (1979)
Kalyug (1981)
Hera Pheri (2000)
Lage Raho Munnabhai
Dil Se
[deleted]
Pyasa.
The Apu Triology.
Ankush.
Vastav.
Shahid.
Lagaan.
Anand.
Dor.
Kaminey.
A wednesday