I would like to write this on the basis of my experience – Indian classical music is melody based, devotional and philosophy based which draws us more towards peace, comfort and meditation, while western vocal is more harmony based, artistic and entertainment based, it does not mean here that we do not get or cannot get peace from western classical vocal music, similarly it does not mean that Indian classical vocal music cannot be artistic and entertaining.
In Indian classical vocal music, mostly used Tabla , after that Pakhavaj is used, in Indian music, talas like Teen taal, Jhap-taal, Rupak taal, ek-taal etc. are used in which people sing showing different types of rhythm. In Indian classical vocal music, tabla, tanpura, harmonium, sarangi are used along with singing and it is mainly sung solo.
Western Music is mainly sung in the form of group music and instruments like piano, violin, drums, guitar etc. are often used for this.