Spooky, what the hell is a yamaha EMX67? I can't even find it on a google search. Microphones tend to be useful for some things, but not others. I use both of the mics you mentioned, and for general use, I would prefer th B-1's. Make sure you get a pair with the same colored dot on the box, because they'll be at least somewhat matched. However, right now, I don't think you're ready to buy anything. You're asking questions, and that's good, but you haven't done enough research yet to understand the answers.
As Lucid pointed out, if your going to use condenser mics, you'll need phantom power. You can get that from some PA mixers, but they're usually very good ones. (read expensive). You can buy a Rolls phantom power supply for about $45, but you would need one for each mic, and extra cables.
What is really unclear here is your signal chain. Yeah, a PA mixer can be used for a recording preamp, or it can be used for live performance. Doing both at the same time is tough, because you have to be able to hear each other without causing feedback, and I don't really see how you're going to do that. Consider getting simple. Get a small mixer, if possible find a small used Mackie. You don't need a lot of channels, just 2-4, with phantom power. Get your live PA, because if you ever want to be *not* a garage band, you need it, with real speaker cabinets. Plug those 2 B-1's into the little mixer (if you have to, even a Behringer will work for cheap) and record the whole band with 2 mics, just like you would in remote recording. Send the main line outs of the little mixer to the stereo line in on your sound card. Use the 58 for the vocalist, and no other mics are needed. The Oktavas would also work fine in the same arrangement.
The problem with using the PA mixer as a recording mixer, is that everything has to get to the board, *and* you all have to be able to hear each other. Sending the drums to the board is a pain in and of itself, and takes several mics. I think it's simpler and cheaper to have your recording signal chain separate from the PA, based on a small mixer and a stereo pair of mics. Keep working on it, you'll get it.-Richie