To answer your first question, yes, given the age of the vehicle, I would inspect all of the hoses, the plastic components and the T-stat. The radiators on the BMW cars these days are aluminum and plastic and have a lifespan of perhaps 7 years. Also inspect the coolant pump as they are prone to failure. I say this not just to be complete in my advice, but to be sure you are an informed consumer. The sender may be at fault for the temp gauge issue, it may perhaps also be an electrical issue in the harness or in the cluster. As to your second question, I an going to respond on the side of caution and recommend towing the vehicle because of the possible implications to the vehicle, towing is usually less expensive than repairing, if you get my drift. Please repost to me if you have questions Dr. Hagerty