The Beijing one was way better. The performance in Beijing was so joyful and showed the Chinese are proud of their culture.The Vancouver was good as well, but winter Olympics just cannot compare with summer Olympics. So the question of which is better, does not make sense at all.
All Olympics opening ceremonies demand a lot of money. But China had to make sure it was very good. What if was not good enough? The western media would be bashing and picking on China.