Hi Darren
Well, 'lurking and luck' is a good start! There's a lot of luck involved in street photography, particularly with night shooting and most of us go through lots of disappointments in order to get the shot. Having said that, when you do get that 'keeper' it's immensely satisfying.
Think of the glass as another 'layer' that can add interest to your shot; use reflections to your advantage to create something with an almost abstract feel. When the glass is misted-up or covered in raindrops it gets even better (look at Nick Turpin's project shot through bus windows to get an idea - you should find it on Google).
It's all about the light. Look for faces in nice pools of light against a darker background, for example - and expose for the highlights (spot metering can help here).
Be brave. Don't hesitate and just get the shot. Most of the time you'll be outside in the darkness and people won't notice you anyway.
As for settings, I use a high ISO and wide-ish aperture in order to get as much light into the camera as possible - and to provide a quick-ish shutter speed.
Finally, look for something interesting in your shot. A couple just eating burgers doesn't necessarily make a good street photo. I think a good pic needs to tick one of 3 boxes:
1. Is it art? Is it lovey to look at because of the light, composition etc? OR...
2. Does it tell a story? Is there a strong narrative? Does it ask questions of the viewer? OR ...
3. Is it funny? Does it make you smile?
.... There's too much street photography out there that is very 'random' - a picture of a bloke walking down a street doing nothing in particular just isn't very interesting!!
Hope this helps - and good luck!
Brian
i.e. I thought I might get punched & the foreground crap has been a pain