With that said, some people have pulled off recordings using just mics and a recorder, with no other power source. Some recorders provide more power than others, for instance I think the Marantz 620 provides about twice as much plug-in power as the R09, but I'd like to know if that's correct or not. The key there though is that you would record from a distance, or record shows that aren't extremely loud, so that you're not pushing the limits of a microphone that isn't powered correctly. You just have to remember that if you try it, it's playing with fire, and you can end up with varying degrees of unnecessary distortion.
As for your original question... AGC off, Low Cut off, and mic gain on Low. I'm sure you figured out that last one on your own, but beginners have ruined recordings by not using the correct gain setting. If you're not familiar with adjusting your recordings in audio editing programs afterwards, then you could try putting the Low Cut on for bass-heavy rock bands, but it could ruin a recording and it would be risky. I've never used it either way but people have posted samples of the internals in the past with the Low Cut on, if memory serves. It's risky and it's not advised, but you could always try it out on local bands/shows that don't mean much to you.
Setting the levels will depend on a large number of factors... how loud the show is, how close you are to the speakers and PA setup, and the venue you're in. I'd start at about 8 if you're going to be close to the sound source, and work your way from there... maybe go up to 9 10 or 11, or even 13, depending how far you are. If you're even further away then you could try to push it higher than that as long as you think the volume is still low, but it's always safer to stay on the low side. The levels really depend on how loud the show is and where you are in relation to the stage and speakers.