Yes they can co-exist. The 2Wire is no different than a wireless router as far as the router part is concerned(except with the 2Wire you'll have a limit of how many wireless connections you can have). With no security of any kind on a "normal" wireless router you can have a mix of 254 wired/wireless devices, it makes no difference. As far as the router is concerned they are all addresses.
My suggestion is if you aren't comfy with it all is to call your provider and have them walk you through turning on the wireless part of your 2Wire. Take notes on the security part but until you get the printer connecting and working properly, there is no need to add to the issue with adding security. You can do that after you are sure it works. This site
has some good info. I couldn't find your exact model but I have a feeling they'll all look enough alike that you can figure it out.
As far as the printer: I read the manual. Its fairly straight forward. Connect a PC to it via USB and run the CD. Click Wired/Wireless devices and follow the on-screen instructions. You will need the 2Wire setup first because you need a lil info.
Again I would recommend getting it all setup and running before you add any kind of security(WPA or WEP). But you will need to set up some sort of security. Otherwise your network will be wide open to other people connecting =)
Its not too hard promise =)
ps. I know you can have more than 254 devices on a network but I was talking about "normal out of the box" home routers =)