I have taken both a basic first aid course and the EMT course. If you can stand cookbook medicine, go for it. If you plan to practice in an area where spanish is prevalent, I'd take spanish instead. First aid is very very basic, and won't help you much in med school.
I didn't take a college class in it, but I am certified in first aid among other things. Getting certified was boring as ****, basically sitting and watching ancient movies and then taking a test. It's not bad stuff to know though and I imagine the college would give you a little more for your money than an ancient movie.
I took it, I loved it. Mine was CPR, AED, 1st aid. 3 credits and a gen ed. It's useful if you understand you probably won't need to use what you learn there- but if you ever do, you really really really will.