I apologize if this was brought up before but I was not able to find it via search. Surprisingly I was not able to find much help on google either. My house has metal studs and I would like to hang picture frames up. In some places I will have only drywall. I assume I should use a plastic anchor and a screw. In some places I will go into a metal stud. What kind of screw should I use? Does it need to go in at an angle so it doesn't slip out? How should I do this?