Best cruise lines, times to go and places?

[AlisonCotton]

I have been on a cruise once before (carnival) and with all the bad press not sure I should go that route. My fiancé and I are not made of money (not even sure we could afford to go!) but id love to try.. What are the best cruise lines and the cheapest time to go? My dad says fall/autumn is cheapest but I'm a nursing student and not sure I could afford to miss a week.. Thanks!! any tips on places to visit also