Absolutely, it's definitely a topic that needs discussing. I've noticed this recently, there's been a run of good documentaries re-examining events in recent history, including Hitler's death or escape from Germany (Hunting Hitler), the JFK assassination (JFK Declassified: Tracking Oswald), Charles Manson (Manson Speaks: Inside the Mind of a Madman) and so on. To be honest, Cortez and the conquistadors isn't a topic I know very much about, but I'll be looking into that this weekend I think.
I totally agree with you about the erasure of certain figures, and it's like you've already said, if we ignore or forget about these events and people, we'll be doomed to repeat the same mistakes. In the past it was the victors who wrote the history books, but now in the information age, hopefully the facts will instead speak for themselves.