the role of games, stimulations and role playing exercises in langage learning
The word methodology has three "o"s. Methodology and role (i.e. purpose) are two different things, so I am not quite sure I understand what you are asking. Could you be a little more specific?
As for the role of games, etc., the purpose is to provide learners with an opportunity to use language naturally (e.g, to get learners to use language in a way that has them thinking/working out the puzzle). Doing is much more beneficial in terms of long-term memory retention than is memorizing.