Nurse Extern at Thomas Jefferson University Hospitals
Nursing programs are pretty rigorous! Your chemistry, biology, anatomy, pharmacology, etc. classes your first couple years, and your second two years involve multiple days a week of clinical hours in a hospital. You won't have much room to double major most likely. I would say a minor in Spanish would be the most useful in nursing, or even if you just pick up an intro class in another language.
I'm a nursing major with a minor in healthcare management, a business minor. This helps me understand the healthcare system in terms of insurance payments, risk management, and other management roles. I really like it!
If you have any room in your curriculum for other classes, fill it with something you're interested in. The greatest part about college is getting to choose the classes where you learn exactly what you want. Learning more about any field can enhance your nursing career in one way or another.