How do I remove my stripped, plastic drain plug?

My radiator's drain plug is made of plastic, with a phillips head piece for removal. I went to change my coolant today, and I have found the stripped drain plug. How would I go about removing this plug. Should I drill up into it? If so, will some of it get stuck there? I plan on buying a new plug from an auto parts store before I do anything, I just don't know how to get this plug out.