Was Christ really crucified?

 

Most likely, yes.

The "scandal of the cross" was actually one of the biggest public relations problems faced by early Christianity. As early as the 50s AD Paul acknowledged that preaching a saviour who had been crucified was considered ridiculous to most people. To the Jews, anyone who had been "hanged on the tree" was considered accursed and abandoned by God based on their interpretation of Deuteronomy 21:23. And to non-Jews crucifixion was the most shameful and humiliating of deaths, reserved for escaped slaves, bandits and rebels against Rome. This is why Paul says that claiming a crucified man was the Messiah was "a stumbling block to the Jews and nonsense to the Gentiles" (1 Cor 1:23). There is no doubt that Jesus' first followers taught that their leader had been crucified and was the Messiah despite this and did so because this had happened.

The second part of the question seems to be referring to the idea that Jesus didn't really die on the cross and was taken down alive and revived afterwards. This is known as the "swoon theory" and tends to have little traction with modern scholars, regardless of their background. One thing the Romans were very good at doing was killing people. They were also very good at making sure crucified people died (eventually). The chances of them slipping up on this occasion and somehow allowing Jesus to be taken down alive are remote in the extreme.

Even if, somehow, this did happen, the idea that the "resurrection appearances" were actually a revived Jesus who had never died in the first place is even more unlikely. In the one case we have of three crucified people being taken down from the cross alive, two of them died soon afterwards. Josephus tells of finding three friends of his who had been crucified by the Romans and begging the Roman general Titus to take them down. Despite being given the best medical care from Titus' own doctors, two of the three died.

So the idea that just a day or two after being crucified Jesus would be prancing around Jerusalem and going on picnics in Galilee is fairly fanciful. He would have been bed-ridden for weeks if he survived at all. There are other rational explanations of the resurrection stories that make more sense than this one.