The Design Museum is a museum in Kensington, next to Holland Park, which covers product, industrial, graphic, fashion and architectural design. There is also a nice cafe on the 1st floor with beautiful views of the park.
The oldest public art gallery in London also is my local gallery in my neighbourhood. Opposite to the Dulwich Park where I walked with my puppy regularly. They have great collections of Dutch paintings as well. My husband found the original Dutch painting of the print at his home he was growing up with.
I'm a big fan of Richard Serra. As this is the train station I use to pass in and out of London. I think it's safe to say i've spent more time gazing and contemplating this art work than any other on earth! The steel monolith sits in a rather petite amphitheatre with surrounding step/seats. During the week, it's packed with picnicking stray commuters. I just love sitting there.