So what makes a scorpion suitable for the "beginner zone"? Generally, anything that isn't a Buthid and isn't terribly difficult to keep, and is also fairly common in captive collections. Common examples include the large forest scorpions (Pandinus and Heterometrus genera), flat-rock scorpions (Hadogenes spp.), the desert hairies (Hadrurus spp.), and a number of Vaejovid scorpions.
--- It should be noted that Hadrurus spp. are easy-to-keep beginners, but rearing juveniles in captivity has proven very difficult ---
What is NOT a beginner? Most Buthids -- see full list of genera below -- are not suitable as beginner scorpions. All medically significant scorpions are in family Buthidae. Among the more expert-oriented species are anything in the genera Androctonus, Tityus, Leirus, Hottentotta, or anything with "buthus" in the name.
So, if there's any question / comments / suggestions on the distinction here, feel free to post in this thread.