Using downloaded NES/SNES ROM files for research work
What is legal, and legally enforceable, varies from place to place - especially for things like scientific study. But there is an additional ethical and respect issue. 

I would suggest that you contact them with your research proposal. As long as it doesn't have competitiveness issues, or encourage activity that they frown on, they might actually support you. Of course it might also set them against you depending on what you want to do, but it is worth considering, at least.