I don't understand your issues with Ruby on Ubuntu, setting it up with RBenv is fairly simple, you can see my build script here: https://gist.github.com/kaspergrubbe/5383877
About 1.9.3 and 1.9.1 are you sure that it isn't about this issue described here: http://stackoverflow.com/questions/8564210/why-are-we-instal... ?