What is a good research experience What kind of research experience is a good or satisfactory research experience for grad school admissions ? There are tons of venues even IEEE has some easy to get conferences which has its name attached to. 

So when someone says he has research experience it is very subjective and differs from reading a few papers about ones field to publishing in national level to mediocre international level conferences.

Also there are places where a professor at a respected institution may get his paper rejected.

So I am totally confused which research experience is really a research experience ? How do you set the thresold ? 

What happens if I have easy to get >5 IEEE conference papers which are may be unheard or new ones such as 2nd IEEE conf on X ? Will I get an edge over other people with no publications or who does not want to publish at such places ? Should I lean towards this approach ?

Good letters from MIT will be a good indicator but what if you have no such recommender or he is tottaly unknown ?
What kind of research experience is a good or satisfactory research experience for grad school admissions?
How do you set the threshold?

There is no threshold.  Instead, graduate admissions committees judge research experience on a continuum.  At one end are things that hardly count at all (e.g., independent textbook study described as research).  At the other end are extremely impressive publications.  Most undergraduate research is somewhere in the middle, and how meaningful it is can be difficult to judge.  To help the committee, you need to explain what you did, why it is interesting, what your contributions were, and perhaps what you learned from it or got out of it (especially if it didn't lead to a publication in a high-quality journal or conference).  It's also important to have a letter of recommendation that addresses this research, to evaluate your contributions.  If you just mention a paper on your CV, without giving this sort of background information about it, then it probably won't help your application much.

Will I get an edge over other people with no publications or who does not want to publish at such places?

It's hard to predict.  Nobody's going to be counting papers or setting thresholds for impact factor.  Instead, the committee will be looking for two key things:

Have you demonstrated the ability to do research?  (Some people get wonderful grades but do not succeed at research.)

Do you have enough experience to know what you are getting into in graduate school?  (Some people think they want to do research, but when they discover what research really involves they change their minds.)


Instead of worrying about thresholds and quantities, I'd suggest focusing on making sure your application satisfies these criteria.