There are a few problems with the Jesus/Dionysus comparison.
First of all, using your search terms you're more likely to find proponents of the recycled Jesus theory. Not really objective information, a fact proven by the link you posted from "HolyBlasphemy.net".
Second, a Greek god dying and coming back to life is very different than the story of Jesus. The rabbi that you acknowledged as existing was publicly executed. He was buried in the same town he was executed in. People began to risk their own lives by claiming that the tomb was empty. That's very significant.
All anyone had to do was go point to the tomb and say "Nope, he's still dead", but that isn't the response that was given. Jewish leadership claimed the body was stolen, confirming the empty tomb. Given the fact that the tomb was guarded by 1st century equivalent of Navy Seals, it's a very unlikely story.
Plus, there is the simple fact that liars make poor martyrs. If you held a gun up to Tom Cruise's head and said "Stop talking about Scientology or you'll be slowly tortured to death", what would he choose? There were many people who not only risked their lives but died on the belief that Christ was risen. Plus, the fact that Christianity spread so fast in a hostile environment.
Not only that, but the reason for the death and resurrection is completely unique.
It's a matter of historical fact and context. Many of the Jesus comparisons to other myths are either re-telling Jesus' story wrong, re-telling the myth wrong, or both to try and make them fit. One can't buy into the recycled Jesus theory and still claim objectivity.