I didn't spend as much time as I'd have loved to but I'm going to try to answer your question, Ajay.
If you love parks, you'd be delighted to know that Bangalore is also known as the Garden City of India. The parks as well as the lakes are both incredibly impressive. For parks, I'd strongly recommend Lal Bagh and there's another bigger one called the Cubbon Park.
For historical places, if you love ancient architecture as much as I do, you'd very much like to check out Bangalore Fort, Bangalore Palace, and Mayo Hall. As for shopping, the two places that I know of are Brigade Road and Commercial Street.
Hope this helps!