I’m doing this from memory, so I assume someone with more facts at hand will correct me.
The Superboy of the 50’s and 60’s was just Superman but younger.
After the Crisis series, in the mid 70s (IIRC), they revamped the whole story. Jor-El and Lara changed their looks (Jor-El dropped the cheesy green outfit with yellow sun emblem on the shirt and got a more alien look), for one thing. Jonathan and Martha Kent were still alive when Clark was in Metropolis for another. And Superman’s powers now came almost entirely from exposure to the yellow sun (prior, his muscle powers were mostly from earth’s lower gravity and his expanded sense were from the yellow sun.) Thus, his powers developed only gradually over time, so that there was no “Superboy” … Superman emerged somewhere during or just after college years.
The SUPERMAN movie (1978ish?) with Christopher Reeve made some minor changes in this, like giving Jor-El the “S” emblem on his robes, bumping off Jonathan but not Martha when Clark was a teen, and having Jor-El continue to be a direct influence via that little green ice thingie.
The concept of Superman being torn between his earth identity of Clark and his Kryptonian identity of Kal-El came into play after Crisis. There may have been some hints of it in the earlier versions, but they were pretty mild – Krypton was just like Earth except “more advanced”. Crisis set up Krypton as culturally different, and the movie set up the polarity (Jor-El arguing that Kal-El shouldn’t interfere in human destiny and Jonathan arguing that Clark should be helping people.)
The comics actually toyed with a triple conflict: Kal-El the Kryptonian, Clark who just wants to live a normal life, and Superman the Savior.
Hence, the current SMALLVILLE series is certainly a departure from the 50’s and 60’s comics. It adapts the post-Crisis version somewhat, by having Clark’s powers developing – the muscle powers are there, but the sense are sort of developing(IIRC, in season one, he first gets x-ray vision… and he still can’t fly, etc.)
The notion of Jor-El urging Kal-El to be Kryptonian is consistent with the movie, I suppose, but Jor-El arguing that Kal-El become World Dictator or something is just… wrong. The whole set up is that Jor-El sacrificed himself (he could have gone in the rocket) to save his son, and that seems completely inconsistent with Jor-El the Power-Mad Dominator. Hence, the speculation that this isn’t really Jor-El… I personally think that’s wishful fantasy. I think the SMALLVILLE writers just decided to take things in the direction of Psycho-Jor-El.