wired or wirelessly?
The way you describe the problem, I'd say the easiest solution is to simply plug in a USB cable from your printer. If you don't have the driver, that's easily solved. In your print menu, there may be a button called Printer. I believe it's from here that you can add new printer drivers (without installing software from CDs or downloads) I had to do this at work when I took my laptop in recently. If the printer is connected through USB or a network, it should appear and you should be able to add it with ease.
Adding the printer this way should allow you to connect without disconnecting the PC, but I'm not 100% sure. I don't really have any experience of mac to PC networks, but it can't be too hard to have a shared printer. Hope this helps.