Even the walmart bikes assembed in-store dont get torqued to specification; their employees aren't allocated propor tools.

That said, areas I commonly see fail on walmart bikes from lack of torque:
pedals -unscrews itself
crank arms -securing bolt drops out, crank works loose
stems -handlebars rotate independantly from fork under high force
be sure to secure these areas 'really darn tight' and use grease

after that, concern yourself with getting the brakes adjusted right; you will probably need to true the wheels first to make this possible
then you'll need to adjust the derailers....
etc
plenty of tutorials on various adjustments online