James has packaged his files as zip collections. There are duplicates in these due to differences in naming and due to the same file being in a year and in a composer collection, as simple examples. In the year 2000 kar and mid zips, there are 68 duplicates when I did a search for them using a duplicate finding program. So if you plan to convert these tunes to mp3, ogg or wma files, you likely should eliminate the duplicates first, so that you save on the conversion effort and computer time. Having converted them, you likely want to inject tags inside them so that your player provides you with better information on what is playing. How to do these things follows:
To find duplicates, go to http://home.comcast.net/~radwen/ and download Midi Dupe Finder v4.6. It goes through the unzipped files and gives you a choice on which duplicate to remove. There will be some where the title includes underscores in one name and just spaces in the other, or where the title is a short form in one instance and full in the other. If this program shows you duplicates, it has compared the inside of the file and is certain both are identical internally.
I standardize the names of the files, to MY standard format, which facilitates putting tags INSIDE the converted mp3 or wma file that is the result of my use of SynthFont. My format for file names is yyyy= title yyyy= composer= music type.extension [kar or mid] so that a song will look like 1909= Wall Steet Rag 1909= Joplin, Scott= Rag.Mid to use an example of a file James just did a day or so ago. To rename files I use Midi File Renamer v4.5, also from http://home.comcast.net/~radwen/ as it shows me the text inside each file, so that I can see the name(s) of the composer(s) and the type of music the composer chose to use. Where rag or fox trot or cakewalk, etcetera, is not provided, I use the word 'song' in that place.
I use mp3tag from http://www.mp3tag.de/en/download.html to inject the tag inside the resulting wma or mp3 file. the =space is my field separator for this program, and I sort files by year, so the year is first, but I also add the year to the title so that it displays when the song is played in my players.
Anyway, these programs are free, although their creators will not say no to a donation... that is up to you.