Once my kids were two and a half I introduced them to the computer. The first attempts were made to try the mouse and pictures were shown on the screen. It wasn't until I heard the Linux Link Tech Show guys interview the lead developer of gCompris that I saw that there's a lot of good educational stuff out there that can greatly benefit my children. The sooner a child grasps certain concepts a better base he or she has to understand more. It's a snowball effect you start the sooner the better.
I set up a PC specifically for the kids and spent some time introducing them to some basics. Bit by bit I added more applications and features. The results were pretty good with my oldest daughter. She got an exceptional score in her last year in kindergarten. She is a very bright kid, but I'm very much convinced the Kids PC has helped her with concepts like groups, numbers, shapes, colors, dexterity, language and abstract thinking.
There is one rule I live by and I want to pass on to my children: Try things that are above your level, it's the only way you will learn new things. I try to have my kids see learning as a positive thing by having them associate it with fun. At the same time I do the reverse by using “not showing a new thing on the computer” as a punishment.
The games I show my children are at or slightly above their level. I don't mind if they can not complete a level or even play the game as it should at first. The first goal is that they try the new software, all the rest is irrelevant. Always keep your primary goal in mind!
I fail to understand parents who teach their kids that learning takes effort and anything that takes an effort is not good. Those children are destined to become lazy, fat and dumb. Not a very good start in live, is it?
If you invest the time and energy to set up a computer with educational software and help your kids use it I'm sure they will benefit from it in one form or the other. Once you get them going you will benefit on the short run - the kids have something to do - and on the long run - they will become brighter people.