#1
I know my minor pentatonic and major and blues scales and stuff like that. but, I've been getting into jazz and know all my basic chords and stuff but when I play with friends the penatonics just don't sound jazzy. What scales do I need to know to be able to improvise over jazz stuff?
#2
stay with the major and minor scales for now. learn to make them sound jazzy. if you can't make major and minor sound jazzy, you won't be able to get the most from bebop scales and such.

remember -- it's not the scale, it's the guitarist.
Anfangen ist leicht, Beharren eine Kunst.
#4
Lots of chromatics. I'm no jazz expert, but I feel like its almost quintessential to Jazz.
Where's Waldo?