I choose the option 2

Just run will probably make sure I'll survive today, but gather some useful itens for tomorrow might be the diference between life and death.

in the others room of my floor may have someone who still have something but he obviously will not want to share, and he/she could become violent, o even he/she could be starving and tried to kill me in order to have the next meal.

I'll have to pass trough the main floor anyway if there is any threat in there I would have to face anyway, so why not take a little time to search for something useful and also it is easier to escape from an attack.