I'm not Will I'm afraid, but
scubasteve:1. how hot does the 805 run. i have heard of problems from other owners. Bear in mind that i am in the tropics so it is already 90F every day although aircon is on normally.
There are wild stories of 905s which run so hot you burn your hand if you touch them - mine runs hot, but you can certainly hold your hand on it indefinitely without fear of scalding yourself! The key is ventilation - I have always had at least 8" of space above it and plenty of room around the sides.
scubasteve:2. the appeal of the arcam or okyno is the simple operation for the wife and family. everything connected via HDMI (DVD, apple TV, PS3, cable HD box). are there any digital amps that excel in music but are only two channel audio/video
I'm not sure about digital amps, but if you're looking for a stereo setup, just ensure you get one with at least 4 line level inputs and connect all the sources up using their analogue connections (running the HDMI or Component leads into the TV for video). Or you could look at getting an external DAC with enough digital connections for the above, input all the sources into this via optical or coaxial, and then connect the DAC into the said stereo amp. Or you could go for both a stereo amp and an AV amp with pre-outs as Gerrardasnails points out - connecting your out and out AV sources like the DVD, HD box and PS3 into the AV amp (for the easier connection) and your music sources into the stereo amp (for pure stereo sound).
At the end of the day, with your setup I can see the attraction of an AV amp in terms of easier connectivity (especially if your TV doesn't have enough HDMI inputs), but for out and out stereo peformance, I'd say a stereo amp is definitely the way to go.
Up to you!