Who is friendly to who? I know the core races are usually friendly to each other, but what about all the other races?
Are there any that can be easily included in a normal group?
My opinion, even though it might be wrong, is that any race's entry that says they are rare or isolated will not have great relations with other races initially due to unfamiliarity.
Races that are traditionally evil aligned (goblins, orcs, hobgoblins, gnolls, drow, etc.) will have a very hard time integrating into the societies of other "goodly" races and will likely be regarded with fear, hatred, etc.
In the Beginner Box, there really isn't any way to play other races.
It's meant to be an extremely limited rule set that only goes up to Level 5, and is primarily an introduction to Pathfinder for those who find the Core Rulebook overwhelming.
If you're thinking about adding other races to your party, you're ready to DM at a level far beyond the Beginner Box.
(clarifying question: are you actually asking a question about playing using the Beginner Box set or are you asking a more general question?)