That's correct.
If you want to jailbreak, go ahead and run Redsnow.
This is the tutorial that you want:
http://www.iclarified.com/entry/index.php?enid=4447
However, DO NOT DO step 2, just go straight from step 1 to step 3.
Note also in step 1, you will use the 3.0.0 firmware to achieve the Redsnow jailbreak, not 3.0.1, so you need to download that one. You will still be on 3.0.1 afterwards.
The worst that can happen if something goes wrong is that you end up having to restore to 3.1 unjailbroken, but this is unlikely.
And just to anticipate one possible glitch along the way, if Redsnow gets stuck at "Waiting For Reboot" in the middle, just unplug the usb cable for a couple of seconds and then plug it back in.