It's a really silly cartoon, but I had every action figure and played with them all the time when I was a kid. And now I'm showing my son the cartoons and I'll give him all the action figures whenever I can rescue them from my parent's attic.
That's cool that you still have them to give to him. My son has already ask that we not get rid of his Imaginext toys when outgrows them. He wants to save them and give them to his children! Talk about thinking ahead!
He-Man was silly, but enjoyable silly, in the right doses. Of course, when your child latches onto something that you used to like, it makes them much more enjoyable to watch. I remember my kids enjoyed Hong Kong Phooey when they were little. As I watched it, I thought, this isn't as good as I remembered, but it was fun to watch with them.