Hi Richard4009
I took my mom last year to HK and we stayed at the Eaton Hotel.
It is a sister hotel to the Langhams, and it really is not in the same star category by any shot, but the rooms are very comfortable, beds and bedding were soft and plump, and the executive lounge for breakfast and drinks was fantastic - my mother loved every minute of it. We booked a junior suite (or whatever it is) with separate living room.
The Eaton is ranked #25 out of 152 hotels in HK, the link with photos is here:
http://www.tripadvisor.com/Hotel_Rev...Hong_Kong.html
All that being said - its not really a place for a 'hotel experience'.
As to your question about the Langham Mongkok - I have heard nothing but the best reviews. I have also stayed in Mongkok, the only problem really is its location to central TST. Most hotels run a shuttle service but you would certainly need to take either the shuttle or the taxi to go shopping. The various night markets are close to Mongkok.
Finally, most of the big hotels have 'packages' which might be of interest. The Peninsula has a couple of days with all sorts of upgrades and inclusions, starting, when I last looked, from USD400 a night. Perhaps consider transferring at the end of your holiday? (although my mom refused to do so... saying once she is settled in that's where she stays!)
regards
lme ff