How to choose a voting system?

We have an election to choose 2 representatives out of 4 contenders in the race and the ballots counted to the total below : 42 of A > B > C > D, 26 of B > C > D > A, 15 of C > D > B > A and 17 of D > C > B > A. I know this is a ranking system, but how you count them can... show more We have an election to choose 2 representatives out of 4 contenders in the race and the ballots counted to the total below :

42 of A > B > C > D, 26 of B > C > D > A, 15 of C > D > B > A and 17 of D > C > B > A.

I know this is a ranking system, but how you count them can really make a different. In one way, I get a result of BCAD, meaning that B and C will be chosen as the reps, but there are also systems where D could actually win (results DABC or DCBA) and another one system with BCDA.

How do I know if my chosen voting system will pick the people's choice? How do you make an analysis with the result above? I can see that most voters pick A as their first choice, he can only get seated in one of the system I have tried, and as a second place at that, too. Any help?