Can I ask, are you unhappy with the images shot, or just the quality that they have been posted at? If it is just the quality of the posts, then bare in mind they are all only about 30-50kb (the original image will be 2-3mb plus) so they will look a bit grainey etc. However, the final prints will be clear and crisp (or should be!)
If it is the overall quality of the pictures taken, then you really need to say to the photographer they are not to the standard you expected. I know you can never recreate the day, but if he's a professional photographer I'm sure he has some legal obligations to you.
There are some lovely shots there, like the one of you with the brides maids in the ring of roses type shot, but I can see there are a few that I wouldn't be happy with either. Some of them are just due to the lighting, and I think turning these into black and white and a bit of editing would sort them out.
I'm shocked it has taken them 6 months to actually put these pics online for you! Seen as it doesn't look like there has been a great deal of editing done to them either.
I don't think pay should come into it if you have gone to a professional photographer. If they advertise themselves as a wedding photographer, they should be profficient enough to provide you with beautiful pictures. However, if you went to a student or a family friend, and just gave them £100, then fair enough, you may not get as many nice ones.