I just bought a Galaxy 7.0 for my wife who is completely computer illiterate, because I was hoping that the OS with its touchscreen user input would be easier for her to learn. (The verdict is still out if that system is better than a conventional keyboard/mouse system of inputting for somebody who is non technical and never has worked with computers. We also do not have one of those newer cell-phones, which would have made the transition somewhat easier. In the mean time I am learning to use it as well!)
Her main desire is to do Internet surfing/shopping and emailing people, and perhaps later on making pictures and watch Internet TV, so it is pretty limited.
The reason for choosing a tablet is the convenience of having a small, mobile device that she can hold in her hands and use trough out the house using WiFi. Also, it is difficult to buy a good complete computer system for $250, which in addition, will require room for the case, keyboard and monitor and tethers you to a desk.