Buckling, Static, or Nonlinear?

Hi all,

I am new to simulations in Solidworks (and Solidworks in general). I am making a drum for a portable toilet, where a force from a seated person is applied to the top rim. I am making a simulation to see if a particular HDPE drum is suitable to purchase for this purpose. I am a little confused about the options when you first create a simulation; should I use Linear, Nonlinear or Buckling? After a google search, buckling seems to suit my purposes, but I wanted to make sure and clarify what each is used for here first, as I tried all three and got different results, particularly for displacement. Also, can anyone clarify the data to help me analyze/make a decision for things like this in general? I have attached some screenshots here. Thanks so much!

SolidworksSimulation