For the first, you need to create a form using your C# (I prefer Microsoft Visual C# 200
. VC# Can be downloaded here; Visual C# 2008 Express Edition
Click Ctrl+Shift+N, write in the bottom "MessageBoxTEST", after that, click like it says in the picture:

In that form, you place a button (using the toolbox), it says how on the picture.

Right-click the button and select properties, then scroll down where it says "Text". Write "RoflBox" there.

Now, here comes the coding..
Double click on the button called "roflbox", when you've made that, it appears a big document where it is some text, no matter of that text. Just write as I say under the following :
Code:
private void button1_Click(object sender, EventArgs e)
{
Now, write this:
Code:
MessageBox.Show("I like RoflCopters");
Also, If you want (I just came up with it now) you can write
Code:
MessageBox.Show("I like RoflCopters", "RoflCopter");
That code will make the messagebox use a title (I think that is the right code for it).
This should look like this:

Now, player around a little with the gui so it looks pretty good. Then push F5. The builder should debug the program so the form arrives, now. Push the button and this should come up:
You have successfully made a program in C#, now go away and say this to your friends and say that they can't do it XD