The receiver is Analog. You can purchase the optional UP-HT1 to pull HD Radio Stations.

The radio tuner is digital. One easy way to tell the difference between digital and analog radios is that analog radios will have a classic slide tuner knob.

I understand this is late, I am only answering it for anyone purchasing it and has a similar or same question.

Depending on a number of factors on how he is using his current TV setup. If he is using HDMI then I would purchase an additional HDMI Cable and using the HDMI switch built into the S3500 so the OSD functions. If he has multiple HDMI, Composite,RCA Etc in use he will need a number of addditional cables or switch it all over to HDMI.
Regardless I would purcahse additional Monster or Similar 16Gauge Speaker wire and not use the wire that comes with the system. Outside of that a good Surge Strip to protect the system. Package comes with most everything you will need.
Speakers do have a Slit for mounting to the wall, you can purchase full motion wall mounts for the speakers if you want to get a better aim for each speaker.

Yes, you will need an hdmi chord that goes from the receiver to the TV as well as hdmi/auxiliary cables that go from your cable box/video games/dvd players to the receiver . The later however should come with those systems but it wouldn't hurt to double check.

Yes, wire is included. I don't know the exact feet, but each speaker comes with its own color coded wire. It is easy to hook up and each length is more than enough, including for the rear surround speakers. If I were to guess I would say the lengths go from about 10 ft to 50 ft depending on the speaker.

i use my build in pre wired for the speaker .

Yes, all the wire is included. Fortuantely, my room is already prewire for surround sound speakers system so I didn't need to use the wires that came with the Onkyo system. However, the wires for each speaker looks like 20-30 ft. I'm sure if you're using this in a small to medium size room that the wires should be long enough.

Hes

Yes it does come with a remote

No, there is no remote included with this product.

The subwoofer doesn't connect to the wall but is wired to the receiver.

Powered

yes

No, this product does not have multiple turntables.

It has Bluetooth compatibility so it should work. However, I've not tried it yet.

no Bluetooth, but there is a front usb port.

yes

Yes this charges the IPAD,IPHONE,I-Device through the USB port.

This system is not going to provide large amounts of loud bass. If you are looking for a system to rattle the windows you will have to spend more money on a better system. That being said, I enjoy my system and it has worked nicely for me.