That would be the second thing to to (the first is kicking the case): open a terminal and do a: ps -A , this gives you a list of currently running processes. You'll probably find a line related to staroffice (maybe writer... don't know).
You have to kill the pending process in order to start a new clean session: do either a: killall -9 "name_of_the_process" or simply a: kill "number_at_the_left_of_the_name_of_the_process" (without brachets!)
[felipe@entropic felipe]$ ps -A
PID TTY TIME CMD
1 ? 00:00:03 init
2 ? 00:00:00 keventd
3 ? 00:00:00 ksoftirqd_CPU0
4 ? 00:00:02 kswapd
5 ? 00:00:00 bdflush
In this case, to kill "keventd" I could do:
killall -9 keventd
(you might want to be root 4 this)
Once you have killed the hanging process you should be able to start staroffice...