Getting a W on your transcript for grad school applications
It is, of course, impossible to say how someone will look at it, but I doubt that very many people would think it odd or unusual. It is pretty easy for students to get in too deep with studies and the other things during undergraduate years. If you drop now and do well later few would think less of you, I predict. 

But if you make a habit of it, then things might be different. 

Since it is difficult to predict the time requirements for research, you have a ready-made explanation for getting in over your head for a term. 

However, a poor grade, such as a D in a major course would be cause for concern. Not necessarily disqualifying but it needs explanation.