My best advice to you is to visit with a trainer and have her/him do an assessment on you and then provide you with a fitness program/plan specific to your needs. Since we don’t know you it would be very difficult to give you any helpful suggestions without any proper assessment. The other think you might want to consider is to schedule a visit with a dietitian and have her/him help you with a dietary plan that is customized for you.
Cardio/strength and swimming are all great, but they will be more effective if they are done with persistency and they are also specifically customized for you personally.
I hope this helps.