Downloading is illegal in almost every country, including India. The Copyright Act of 1957 (amended several times) criminalizes the unauthorized reproduction and distribution of copyrighted works. While enforcement against individual downloaders is rare, uploaders and site operators face severe penalties, including fines and imprisonment.
Believe it or not, official DVDs of "I, Robot" released in South India sometimes included a Tamil audio track. Check second-hand markets or local sellers. Better yet, support re-releases by studios like Excel Entertainment or Apollo International. I Robot Isaidub