If standing, i cross r leg over l and point toes to floor. when moving back to normal position, i hear/feel popping sensation in my groin. any ideas?

Likely no problem.: You might have som crepitus, or crackling in your hip joint from joint ends grinding together. This can be a sign of arthritis, especially if you are older or did a lot with your joints, i would watch for arthritis in the future if i were you, but right now it is likely due to the unusual thing you are doing with your leg(s). Try not to get into these kinds of habits.