can't get subtitles to work

[jonnyD]

I recently downloaded Robert Bresson's "The Pickpocket". It's an .avi file.
The accompanying SRT files did not have englisg subtitles and since I am not fluent in French, I wanted subtitles. I was surprised to find a site that had the english subtitles to download, which I did. The file is labeled:
DivX 5 - 576 x 432 @ 25 - French separate subtitles Englis

I dragged this file into the same folder as the .avi file and hoped to see subtitles but nothing showed up. Is this an incompatible subtitle file? Is it actually a subtitle file at all? How can I get the subtitles to read in english? Or where can I go to get a compatible english subtitle file and how do I get it to work with the .avi file?

I am totally new to this whole thing and would love to know where to go to get the basics on the differences of video file types, which is better quality, when I convert what do I sacrifice/gain from one format to the next, how do I know what subtitle files work with what?

[Baldrick]

THe dvd has subtitles, http://www.amazon.com/gp/product/B000BB14IA/imdb-adbox/ , just buy/rent it instead.