It really depends what Marshall you've got, ie solid state/all valve etc...

For me, I've got an all valve 30w Marshall combo,and I keep the preamp volume down to about 2.5, and the master volume up to about 5. I then use an overdrive pedal to drive the amp. I keep the drive on the pedal to about 6, and the level to about 4. For the EQ on the amp, I use Treble=4, Mid=8.5, Bass=7. I also keep reverb quite high up at about 7. I find that this, coupled with a bit of compression gives me the perfect sound for the Stranger/These Days era. Especially when played using a strat!!

If you haven't got any pedals though, Total Guitar had a poster a couple of years back showing amp settings for loads of players, and for playing Bad Name, they suggested the following settings:

Drive = 5
Treble = 6.5
Mid = 7.5
Bass = 4.5
Volume = 7
Reverb = 2

Bare in mind though, that modern amps tend to have a lot more treble than older amps, so if it doesn't sound quite right, try rolling back the treble and boosting the mids a little.

Hope this helps.