You can play fallout 1 and 2 already with a reasonably fast android device. Just checkout my Dosbox Turbo thread below
[Guide+Video] How to Play PC Games on Android with DosBox Turbo
[Guide+Video] How to run Fallout 1 & 2 on Android with QEMU
I know I have played with DosBox under Android and tested Fallout 2 but on my Neuxs 4 it is quite slow. I am now trying different resolutions for Planescape Torment to see witch is better for my Nexus.