I had 10 Ws on my transcript and was not asked about it in my interviews. I brought the subject up at the end of the day when asked if there were any comments that I would like to make about my application. Two of my interviews were open file.
I don't regret withdrawing from classes. I explained why I dropped groups of classes - changed majors, extended jury duty, over extending myself on two occassions. Hopefully, you didn't drop a lot of classes just because your grades were low. If you only dropped one or two classes, then I doubt it will even be brought up.