About 1/3 of the Palestinians were known to have been taking part in hostilities when they were killed. About half were known not to have been taking part in hostilities when they were killed (this does not included those who were "collateral damage" in targeted killings). Meanwhile, about a quarter of the Israeli deaths are Israeli soldiers who were killed. Unfortunately there does not seem to be a breakdown of how many of the killed Israeli civilians were participating in hostilities at the time of their death.
source:
http://old.btselem.org/statistics/english/Casualties.asp