DD2.5 started using a computer around 10 mo when she was tall enough to pull up to the couch where my laptop sits all day. First as a baby she figured out that if she clicked the mouse a song might start again (as the mouse cursor was often left to the original place). She slowly learned more and before two she was quite independent with keyboard and could use it for example to play starfall independently. I think two months ago she figured out how to use the touchpad mouse. I thought of buying a mouse for her but as I hardly ever use my computer on a table I did not think it would get much use. I was not even sure if I wanted her to use a mouse. We had the click start computer too. I hoped she would not mess around with my computer that much. We got it when she was 11mo. She did not like it at all but she is one of the kids who wants the real thing. She does not like toy phones either. She actually asked Santa to bring her her own mac (I wonder why santa forgot LOL).
Now she uses computer as independently as possible for a child who does not really write yet. She likes to type with word, use skype to call grandma, browser for internet and iTunes to listen to music. I set child friendly bookmarks for her. Usually everything goes well although I need to remember to monitor carefully what she does. Today while I was cooking she was trying to find her email (I guess she thinks she needs one too) and tried to type email on google, did not get it quite right and ended up on some japanese discussion forum. I had no idea she knew about google.
She has always been gentle to the computer biggest problem has been a messy screen.