Oh yes, the temples there are really beautiful. I recently went to Bangrak Pier and can say that boats are really the fastest option. The most convenient way is to take the Chao Phraya express boat from Saphan Taksin, because it makes no unnecessary stops and quickly takes you to the waterfront area. There is a good review of Bangrak Pier on blog.gettransfer. When I bought a ticket, the boats ran every few minutes during peak hours. Tickets cost about 25 baht, which is very cheap compared to a taxi. I recommend buying a ticket at least 30 minutes before departure, especially if you are traveling with children, because the queues on weekends can be quite long.