PROPOSALS for two medical hotels, which would give patients an alternative to prolonged hospitalization, will be presented to the State Commission on Hospitals and Health Care for approval in the next few weeks. The medical hotels, which would be similar to the cooperative care units established at hospitals in New York and Philadelphia, reflect a trend toward finding ways to cut the cost of health care. The hotels would also be designed to give qualified patients a more attractive and independent environment while recuperating. Groundbreaking is scheduled in New Haven in June for the Temple Medical Hotel, a seven-story, $12 million building that will accommodate 150 patient-guests, said Dr. Alvin Greenberg, a neurosurgeon and a proponent of the medical hotel. It will be owned and operated by the Temple Medical Center, a private, out-patient facility.