Bluray is only any good if you are really fussy like me and like watching movies in high definition, sounds like you may need to clean your dvd players laser and also when you hire a movie get them to re coat the disc, this is what I do as I got sick of going back and forth to the video store years ago.
Bluray is excellent on bigger tvs, anything smaller than 32" and I don't think you would notice much difference to be honest.