Fixed spools are the easiest to use and given a little tlc will last for a long time.However they do tend to be a bit on the heavy side
Alveys .Ultra dependable and super simple inner workings . As Zac has said they are best with the reel mounted low down on the rods butt.Can be a bit clunky to use.
Freespools. When you hit a good cast with a freespool just so so sweet .Take a while to get used to but NO line twist and will last for ages ( eg have seen a 20 yr old abu still being used ) I have all of the reel types and use freespools 99% of the time.Can be used with the reel wherever you like on the rod.
The other thing to consider is the rod you have or are planning to use.Theres plenty of rods for fixed spools but not a lot for the others.