For Dire Straits, listen to "On The Night", the live album.  It is a good mix of songs from their various albums, and it will give you a place to start, depending on which songs stand out to you.  Also veru good lap-steel on those songs.
Otherwise, I would just start at the beginning of the catelogue and move forward... they aren't a group that has so many albums that you can't plow right through.  There are a fair amount, don't get me wrong, but as I sit here thinking about my favorite songs, none of them are congregated on any one album, so its kinda mix-and-match, unfortunately.