Does this mean I only get to deal out damage to two of the targets or do I get a minimum of one for each target?

You get to split the 2 damage between the three targets. Thus, you can only damage up to 2 of them by splitting the damage 1-1. If you prefer, however, you can give both clicks of damage to one of the three.

You can deal it out in 10 ways:

Target
A-B-C
1-1-0
1-0-1
0-1-1
0-0-1
0-1-0
1-0-0
2-0-0
0-2-0
0-0-2
0-0-0

I think that's it.