Most parents would like to get their kids to learn golf. It is a game you can play all your life and use in business. It builds character and teaches etiquette.
Don't expect or demand a lot from your child the first time. Kids don't care about score or technique. They just want to hit the ball and have FUN, so let them. You'd be surprised how fast they catch on. They rarely get frustrated unless a parent tries to change them to do it a different way. The most important thing to remember is that golf is just a game. So keep it fun. Golf will hook them without our help.
As far as age goes, look for two things. One is the child's interest level and attention span. If it is something they want to do, they'll let you know. To play good golf you need speed, so your child must be strong enough to support the club and swing it fast while under control. There is no right or wrong age to start golf. Many good golfers took the game up late. Greg Norman was 16. Calvin Peete was 21. Larry Nelson was 23. They all had great careers. Paul Azinger never broke 80 until he was out of high school, yet he went on to win the 1993 PGA Championship. I have helped 3 yr olds that had an attention span longer than a lot of adults.
The biggest mistake I see with parents is (with all good intentions) they try to build a champion too soon. First off, no one likes to be told that their actions are all wrong. They need encouragement instead of correction. When your child wants help they'll ask for it. I have seen plenty of kids ask their mom or dad to watch them swing. That's what you want. I like to play games or challenges with younger kids. Putting is a great way to do this.
There have been plenty of kids that had all the talent, money, instruction, and support that never came close to what Tiger has accomplished even at a young age. Junior camps and clinics are great and especially playing with a friend helps. Just sit back and watch.