1) Trip across the harbour on the Star Ferry.
2) Take the Peak Tram up to the Peak.
3) Personally I love taking the no.6 bus to Stanley market. The market itself is ok for a mooch, some nice restaurants to grab a bite to eat, but it is the bus ride that is the must. Catch the 260 back to Central to save time.
4) Hmmmm....... Wonder along Nathan Road in Tsim Sha Tsui......but you could really take or leave that one.
5) A Tram ride - is very cheap and good fun, catch one on the north side of the island (Central, Admiralty, Causeway Bay) going either way, then when you have had enough, get off, cross the tram tracks and get on one going in the opposite direction.