Days 1 and 4 - Cleans and push press and Straight-leg deadlifts
Days 2 and 5 - Squats
That was former BYU strength training Coach Stiggins' workout.
But that's when I was in competitive shape and had more time for working out.
Now, cardio is more important for longevity and quality of life and weight control. The chest (no bench, just dumbbells), arms, abs, and (wimpy) leg lifts and exercises keep things chiseled.
The OP stated he only had 30 minutes to exercise.