I would like to develop applications using c or c++.
but i have no idea how to start with it, i did try the search engine but didn't get a satisfactory answer. can i get some ideas and examples please:-/
Searching for tutorials on the Internet is one way, as Fbody has already shown.
There are a lot of resources to be found but, as you may have discovered, there's also a lot of chaff, which can make finding good resources a time consuming challenge.
Have you looked at traditional books? I'd suggest doing this because generally they undergo a higher level of scrutiny than web tutorials, typically by a professional editor and publisher. Most of the junk gets removed for you :-)
There are a great many available on the subject and you can find a review of a few right here on Daniweb...
Try to find one that's targeted for your specific development environment and platform, if possible. Otherwise you might find some code examples won't work as expected, which can be very frustrating for a beginner. Until you've mastered the basics of a language, you may not be equipped to solve such problems.
You need Java Virtual Machine in order to execute a jar file. You can associate jar files with JVM, or just right click on it, then click on "open with" and select java. You are looking for 'JRE', Java Runtime Environment.