[Tyfon]

Accommodation: Dynasty Inn is almost as close to NP as Nana Hotel, rooms small but clean and quiet if you get one around the back. Respond to emails promptly for booking (but send deposit payment details via fax). Check the ventialtion port in the bathroom - found 20bht there last time when I was hiding my own cash. No safe in room, leave valuables in deposit boxes behind front desk. Girl friendly - 1 girl at a time (other wise a charge), girls must leave ID at desk.
Manhattan, Soi 22 (I think) - about halfway between NP and Soi Cowboy which is useful (half an hour's walk between the two, typical metered taxi 30bht Manahtten-NP). Also close to Thermae, and Beer Garten (Soi 7). Don't respond to emails, didn't fix broken air con, but rooms large and otherwise comfy. In-room safe. Staff completely ignored my comings (no pun!) and goings with girls (one at a time, no ID, no guest fees) at all hours. Limo. from airport 650bht.
Many BMs have recommended the Majestic Suites - might try them this trip.

Transport & shopping: Cabs okay - make sure you get the journey metered as this saves any misunderstandings on 'agreed' prices at destination. Also less-regulated Tuk-Tuks and suicidal motorcycle taxis if you feel lucky.
Skytrain will get you to many points of interest from Sukhumvit (Nana station etc.). National Stadium will put you outside MKB (MaahKongBoon) which is a HUGE repository of electronics (esp. phones and digital tech.). Before that is Siam Square for other (expensive) shopping and ogling the university girls in their white blouses and short skirts 8^). Also Central Station for pratunam market for less expensive goods and forgeries and the Big C (groceries, clothing).
Change at Central to go north to Mo Chit for the weekend (chatuchak) market. Head South-west to Saphan Taksin (end of branch) to pick up the river tourist boat. For 75bht you get unlimited travel up and down the river by tourist boat (TB) and waterbus (WB) and you get a useful map and guide. Take the TB first to see the sights, get oriented and listen to the guided commentry in broken, sing-song English (Wat Arun is best photographed from the river in the early am). Then hop on and off at will. Wait for the TB if the WB are too crowded. Piers are near the National Museum, Chinatown, Grand Palace, the antiques mall and the principal Wats (temples). You need to get off at an East bank pier and get a cross-river ferry to visit Wat Arun (5bht transfer ferry each way) and the Barge Museum (incl. TB ticket).
Otherwise use metered taxis and buses, just use common-sense as you would in any city. Watch out for ladies-only buses - you won't get shot for getting on one, but you'll be expected to hop-off pretty quick.

Safety: I find Krungthep very friendly and safe, bearing in mind you are a foreigner and easily distinguished from locals, so you stand out, especially if you wander outside the tourist areas. This is not unsafe providing you deport yourself with confidence and and respect for others. Beware of the same dangers you expect in any big city and avoid confrontations - just smile and back off. Don't go with taxi (cab/TT or bike) drivers who promise unequalled experiences at massage parlours or strip shows etc. - you're just asking to get ripped off at best or robbed or worse. But mostly you'll find things very laid-back and wonderful. Learn a few of the nicities in Thai, like "hello", "excuse me", "please", "thank you" etc. You won't stay alone for long 8^)

I'm planning my third trip to Krungthep for most of August with side-trips to Ayatthaya and Kanchanaburi (Kwai bridge and War Museum) and some scuba in the south. Maybe we will trip over one another.

Cheers,

K.