6 Answers

Information here.

http://vox-vocis.hubpages.com/hub/Teaching-pre-school-English

SESAME STREET is pretty hard to beat as far as teaching goes......

Suggestion:  Read with your child and tell stories with your child.  Interact with your child.  Don't plop your kid in front of a computer.  

help the 4 year old read it a book  or let it watch children s shows

We love Teach Kids English http://www.teachkidsenglish.com/.  It's interactive, fun and very effective. Our 4 and 5 year olds love it. There is lots on the net that are just worksheets, but this was the only complete course we could find. Do recommend.

I don't know about online, but there are several educational programs adn games that you can get him. Just pop them into the computer, then give him a little guidence on how to run the game.