Baluns for HDMI generally require 2 x ethernet cables. Some of these include the ir signal too. It is also possible to extend usb over ethernet which might allow you to have a usb DVD drive in your entertainment area. However, you would need lots of cat5/cat6 cables for this kind of setup.
Hope this helps.
There are numerous HDMI-CAT6 converters that will work over a single CAT6 cable now. But generally they are more limited on distance between sender & receiver - less than 30m in some cases.
We have tested a number of USB over IP adapters and none have worked reliably enough for general use in a 'real installation' - and none have successfully supported data storage devices. So my sense is that these usb/IP adapters are really not a viable solution right now... they may be in the future at some point though.
All the best