"I've began thinking that it would've been better to not have seen the movies and just let imagination do the work. "
I agree, although not because I dislike the movies - I just think it doesn't work as well in cinematic format. In the books, you get a much better feel of the day-to-day wizarding world. In the movies it's more of an adventure. In the books, having each year take place in the same place made perfect sense - after all, it is a school. In movies however, that seems redundant and repetetive somehow. I really wish it had stayed in literary form.