By all means yes. Though rental cars can be surprisingly cheap in winter, it might end up being cheaper to bring your own car. And you can bring a lot more stuff from home than you could by plane. Also it might just be more comfortable to drive the car that you are used to. In fact, most of the winter guests in the Algarve that will stay over two months come by car, and make a few stops during their trip. They don´t drive too many kilometers per day and thus have a mini holiday, visiting places like Normandy, Bordeaux, Madrid, Salamanca, Santiago de Compostela, Lisbon, Seville and many more.