mmmm for some of your problem, i'm guessing you should clone your OS.
get a good size SD (2+ GB). install all the programs you usually install in your tablet.
then you can clone and boot from your SD and play around. If you mess up, just copy everything from the tablet.
Edit (heh i guess fatalsaint beat me to it. anyhow, i think install-tools is the easiest way to go)