I would like to have a safe "Linux-like start/boot from DVD or USB stick" environment.
How to do such security thing for the latest OS X (10.9 Mavericks)?
I'm not sure how to make a live environment from a DVD, but it is relatively easy to do it with an USB flash drive or an external HDD.
To install it to your HDD or flash drive do the following:
Also, note that you already have a recovery partition.