I think it's true that you should make sure a college is accredited, but quite frankly I would make sure that is the case on the website before even making it to the school to be there asking questions in person in the first place. Some questions to consider:
*What are the strengths of your _____ program?
*What opportunities are available for internships?
*Are professors required to hold office hours, and how many hours per week are they available?
*if you're considering majoring in science, ask about research opportunities, and lab facilities.
If you're planning to go to a residential college and live there, I would also ask questions such as:
*What percentage of students live on campus?
*What types of activities/events take place on campus, and how often are events held?
*What is the food like?
*What are the hours of the library?
*Is wireless internet available on campus/in residence halls?