Without the aristocracy of Europe, the world would not know the great artists and musicians or the Renaissance.  In fact, the concept of supporting the Arts still exists today; the wealthy of a nation are important to the existence of this still, as well as much more that is desirable.  

I don't completely agree with the previous post.  Feudal lords were able to help bring the Renaissance about to some extent.  They were able to patronize (for example) artists who were instrumental in bringing the Renaissance about.  In this way, they might be said to have helped with the Renaissance.

I would say not much at all, if any.  The best way the feudal system helped the emergence of the renaissance was by coming to an end.