Originally Posted by gulliver
2.AmigaOS 3.1 (ClassicWB P96) - Some eye candy and plenty of handy programs
3.AmigaOS 3.1 BetterWB - For enhanced performance (it is speedy)
4.AmigaOS 3.9 + BoingBags - For having the latest OS and its built-in packs
5.Aros 68k - just pick a stable cdrom image (not ArosVision, because it is not designed for real amigas)
6. AmigaSYS 4 - Like Amikit but less bloated and designed for real hardware.
No Linux? I ran Linux on my A4000 back in the day and it was pretty nice. I'm pretty sure Geert Uytterhoeven is still maintaining m68k.
FYI this was a great introduction to Linux for me. There was no proper distribution, I had to roll my own from source.