DR/DRmin/DRmax are just used to reorganize the data, either ascending or decending dynamic range measurements of the search results.
Lossy = compressed format, e.g. mp3
lossless = uncompressed format, e.g. flac, redbook
The lossy/lossless refers to data compression of the format, not to be confused with dynamic range compression of the recording.
The albums with wider dynamic range (higher DR #'s in the database) generally tend to sound better on good sound systems, but you may want to play the compressed, "loudness wars" version in your car.