Originally Posted by RickJ
Wa laikum Salam
1. As-Salamu Alaykum is "Peace be upon You" but the entire greeting is As-Salamu Alaykum Wa Rahmatullahi Wa Barakatou which means "Peace be upon you and the mercy of Allah and His blessings"
2. Yes, that is one way it can be written. Another is As-Salamu Alaykum and the y in Alaykum is sometimes substituted with an I (in either spelling the first or the latter)
3a. I am a muslim and I would accept this greeting from you or any non muslim for that matter as many muslims should.
In Al Qur'an it says in 4:86 (Chapter:An-Nisa verse:86)
"When a (courteous) greeting is offered to you
, meet it with a greeting still more courteous, or (at least) of equal cortesy. Allah takes careful account of all things. "
Example of this is: If Someone greets me with As-Salamu Alaykum I can either say Wa laykum Salam which would be offering a equal greeting back or I can be more courteous and say Wa laykum Salam Wa Rahmatullah or invoke the entire greeting.
3b. There are no instances that I personally feel you cannot invoke salams on a muslim for it is not a derogatory term, so it should not cause any offense and be accepted. In my opinion it actually helps break barriers and opens lines of communication (even thou our religions differ) where misconceptions or whatever else can be addressed.
Hopes this helps