I am divorced and I am thinking of getting married again. Do I need my parents permission? Also the girl who I want to marry has no family; her mother died 2 years ago and was the only child, her mum's parents are not alive. Also her father left her mother and moved to another country and she has had no contact with him for the past 16 years. She has no other brothers or sisters. She will be moving to my country to marry me. Would my nikkah be valid if I take her to the mosque and get the imam to read nikkah with two of my friends as witnesses?
Short Answer : Yes
Detailed Answer: If a person is a Muslim, baaligh (mature), aaqil (sane) and free (not slave), he can be a witness to a Nikah.
There must be at least one man and 2 women, or 2 men as witnesses for the Nikah to be valid. If a dispute takes place regarding the Nikah, then the Shari'ah laws will apply (atleast in Muslim countries).