Query about visa

Hi,
 I have my visa approval letter etc and am supposed to be entering Vietnam for 2 weeks on 20th January 2015.
 I need to know if
 1. Do I need to fly into Hanoi, or can I fly into Ho Chi Minh? And
 2. Do I need to fly into Vietnam or if it possible to travel overland into the country.
 I would appreciate if you could get back to me asap.
 Many thanks,
 Ps also I only have 1 passport photo... is this enough or do I need to find somewhere to get more taken?