You can always try the hop on/hop off bus there. It takes you to most of the major points, and there is a stop right outside of the Petronas Towers. I would actually go up to the KL Tower over the Petronas Towers since you get a great view of the latter. China Town is very cheap there and is a good size. The bird park was interesting.
There are plenty of places to eat good food. If you're not feeling adventurous, the Pavilion has over 70 places to eat from Din Tai Fung to countless other cuisines from West to East and everything in between. You can easily get to the Pavilion by walking underground in the AC. If you prefer street food, Bukit Bintang is vibrant with a ton of offerings. It's great to visit at night. Plus, my wife said she got the best Thai massage(better than Thailand itself) in all of our SE Asia travels. I believe it was around $20 USD for 1 hour.