A friend of mine faced this problem. She got a requirment in her project to run a few shell(DOS) commands. She discussed this problem with me, but at that time I was having no idea how to do it, so I did what every developer does.............googling.........;)
I found various article on this topic, below is the link of few of them :
Very good article at C# Corner by Dipal Choksi:
Another good example at Code Project by Shilin
Lastly, another code project example by Xiangyang Liu
I hope any of you guys facing same problem, these articles will be of a great help.