You need to enable File and Printer Sharing in Windows 7's Control Panel>Network and Sharing Centre. I recommend disregarding the Homegroup method and sticking to conventional networking. Scroll to the bottom of the page and untick the requirement for passwords.
The Apple gear should recognise the network WORKGROUP and join in straight away. Any other computers running Windows will have to be set up individually.
I'm no expert on Apple products, but I was under the impression you could only use specific printers w/ iOS devices. I have an iPod Touch, and I’ve never seen a printer interface of any kind (no drivers, no setup, no options, no nothing, it’s like printers don’t exist in the iOS world). As far as I know, you need something like Apple AirPrint and a compatible printer.
But again, I'm not an expert on this topic by any stretch. I just know this has always been a shortcoming of (and hassle with) all these iOS devices. Apple makes it as difficult and convoluted as possible.
Good point. I'm equally, and quite happily, ignorant of Apple products and did wonder whether printing was possible from an i-Phone when even my Android can't do that. However, having always been told they were flawless and capable of everything, I may have over-assumed in giving my advice.