It was worse (or almost as bad as) Dragonheart 2. Spoilers below.
The characters were pure cliche, there was the generic bad king, generic bad knights, generic bad knight that is actually good knight, generic poor but helpful people, generic wise men, generic random people know all legends and all happen at just the right time for the plot to happen... I could go on. There was no real character development in the film at all.
The plot seemed to make little sense, everyone kinda wanted the same thing as the baddies did. The setting seemed.... I'm not even sure, there was Roman's and Hadrian's wall but kings and knights, I'm not good with history at all so I may be moronic here but that doesn't seem right in my opinion.
Then there was the WTF moments:
Dragon was inside meteor along with eggs despite being larger than meteor.
Meteor landed with smash but area around it had no burns or trees down or anything.
When dragon shared its heart, it then said it gained speech through that... however in first film Dragon could already speak before sharing heart. No continuity.
Dragon eggs used as grenades... seriously?!?
Dragon pretty much allowing some of the eggs to be used and killed.
Dragon being cursed to only be in shadows yet that gives him the ability to travel from shadow to shadow... and then that power transferring to the human he bonded with!
Dragon being cursed to only be in the shadows yet it somehow turns him evil too.
Slapstick comedy where human and dragon were hurting themselves to hurt the other and dragon mentions how it has armour plated... you know.
"The power of valor breaks curse"..... "Time to curse you again". I mean what the hell!!
The film just made no sense to me, it was badly written with a forced plot, acting wasn't too bad and neither was the CGI, but I just couldn't help but laugh at how bad some parts were.
Now with there being preproduction of a Dragonheart 4 set a little before the events of the first film, I'm not sure how much more they are going to ruin the original and best Dragonheart.