Salaah behind an Imaam who made one Salaam

Q: I am in Oman. When I went to perform my namaz in the musjid I was confused with the way the Imam performed his namaz. The Imaam came and stood on the musallah and without raising his hand up he said allahu akbar and started praying namaz and at the last rakaat the Imaam said only once Assalaamu Alaikum wa rahmatullahi and moved his head right and left with one salaam. Is my namaz behind this imaam correct? Or what must I do?

Urine problem

Q: I m suffering from an illness of urinary dribbling (urine drops coming out). I want to ask you that if I am out of my house and after urine I feel urine drops, can I wash the affected area of cloth with water for Namaz or I should have to change clothes for Namaz?

Marital problem

Q: Me and my wife had been married for 5 years. We have two kids. She is a very caring and loving wife, but due to some unwanted silly reasons, she can't accept my family members and wants us to stay away from them. We have a fight between us most of the time for this reason that she wants us to get separated from my family. Now she is even asking for divorce if I can't stay with her accepting the fact to exclude my family members from our life. My father, mother, brothers and sister hadn't done anything to harm her, but still she doesn't understand. Moreover I feel like she is trying to follow her mother, who has done the same thing with her father's family. But since her father was silent and listening to her mothers decision all the time he accepted it. But I am not able to accept this method of breaking relations. Kindly do let me know, what shall I do. Should I continue with her and break my family relation or accept her request for divorce?