Studying mutations on residues

Hi,

I've docked two proteins and I 've found some interesting poses.

My aim is to understand the real influence of these poses in the interaction. So I'm thinking  to mutate some of them and redock the proteins.

How can I compare results (before and after mutations) so to get importance of mutating residues in the binding surface?

Is this an effective way to analyze the effects caused by the mutations and have an idea of the weight of residues in the interactions?

How can I mutate residues?

Thanks