djm99 
With certain files any disc (DVD-R is the only universal compatible media type) burned for data can transfer some things to the Xbox but there can be weird exceptions and problems because of the formating. Ideally you should create the disc from a XISO file ie. Xbox ISO using the Xbox utility Qwix or C-Xbox Tool v2.7.
Alternatively find a <4GB flash drive which is Xbox friendly (many are not) format it to FATX and use that to transfer any small files to your Xbox.
You'll of course need a Xbox USB adapter and install Xplorer360 on your PC too.
BTW any JPG/PNG can simply be renamed with a .tbn extension and it will be displayed by any XBMC version.
