Actually, your friend has the right one. The Pentax K-x is certainly one of the simplest and most straight forward cameras to use. He is going to need to experiment with it to become more familiar, just like he would have to with any new digital camera.
There other options in the large-format arena, including SLDs from Olympus, Panasonic, Nikon and Sony. Panasonic's SLDs seem to have the most point-and-shoot like interface, if that is what you are after, something like the G3.
Sony's are not reputed to be very usable except for the NEX-7 which has enough customization options to make it usable. Sony does one thing very well which is provide an exposure-priority display on its SLDs. This means that you see the image as it will be exposed before taking the shot, something that DSLRs cannot do through their optical viewfinders. Other manufacturers do this too but not Panasonic and not so consistently.
Inevitably, it is either the latter or bulk which disappoint people moving to a DSLR. The final option is a Canon G1 X which is actually a near-replica of their prosumer compact but with a large sensor. Maybe this has a psychological effect but I do not think it is simpler than an entry-level DSLR. Compact cameras are rather complex now with all the features they offer!