This is a tough question. If you are just starting out, ANY racquet will do. No need to drop $100+ on a racquet until you know how you play and what you like. My first racquet was borrowed and was made of wood. My first “real” racquet was $20 and I got it from Wal-Mart. I wouldn’t spend any real money on a tennis racquet until you have decided to pick up tennis as a sport. If you are just going to hit the ball around with friends 1 or 2 times a year, for about 30 minutes, any racquet will do.
After you have decided to really give tennis more time and effort, you will want to upgrade your racquet. Check out this video from Tennis Warehouse to learn the differences in racquets.