Can anyone tell me the best way to export blocks from Drupal 6 to 7?
Boxes? Features? A Straight field for filed export?
Assuming they are straight up Blocks with body content (not View blocks or other contrib generated blocks), I would create a module that scripts and creates them on install. If you have many blocks, do them in small batches (breaking them up across update_n hooks).
That way you can also test them in small batches and get it right. Once up, you can disable the module and remove it.