grml2ram copy medium to RAM and run from there (see F5 for alternatives)
grub boot GRand Unified Bootloader (GRUB)
dos boot FreeDOS 1.0
- bsd boot MirOS BSD
hdt boot Hardware Detection Tool
+
A list with all supported boot options can be found on the CD at
/lib/live/mount/medium/GRML/*/grml-cheatcodes.txt