You are not giving us very much information to solve your problem. What OS and version of Elements are you using? Please give us more details of what you are doing when the crash happens. Are you able to repeat the problem every time you perform the same action? What tools are you using to make the cutout? Are you in a Guided Edit or using the Expert Mode?
If this is a problem that has only just started, try resetting the preferences file. Go to Edit>Preferences>General tab and click the Reset Preferences on next launch button.