HD Upgrade

I’m looking for an easy way to organize my digital movie collection.
Backstory:
I have about 2500 digital movies i’ve collected over the years. over the past few months i’ve started updating all the 480p movies to 720p whenever i notice its available. Since the new 720p movies are often even smaller file size then my dvd rips.
Problem:
I’m getting alot of duplicates becuase when in doubt i just download the file. Also my xbmc library is getting really messy with all the duplicates.
Questions:
-Is there a fast way to show if i have a movie in hd or not? -Is there an easy way to remove the lower quality of all duplicate movies in my xbmc library?
-Is there a way to automate downloads from this website? Justification:
I’ve done a fair bit of googling on all 3 of these questions. Unfortunately i’ve come up with nothing. I’m hoping someone out there reading this has had similar problems and; being smarter then me, found a solutions
Answer #1
question 1 : depends on the naming of your files …. if you have a movie (some title) and the file is called st_wbrp.avi , and the same movie in 720p, and this file is called : some.title.2013.720p.mkv , good luck then ….
way out : make yourself a little script that lists all the files and you can then give them a title , then sort the whole thing and have a delete (unset) behind it, and that way you can clean house … but without a database in the backend and some manual work , no chance
question 2 : dont know xmbc
question 3 : no