Issues with homework

Having issues with parts of my homework in C# and am using VStudio 2008. Here's the assignment:

Create a Form that contains a guessing game with five RadioButtons numbered 1 through 5. Randomly choose one of the RadioButtons as the winning button. When the user clicks a RadioButton, display a message indicating whether the user is right.
Add a Label to the Form that provides a hint. When the user's mouse hovers over the label, notify the user of one RadioButton that is incorrect . After the user makes a selection, disable all the RadioButtons.

Right now i have the form up and the radio buttons thrown on there. The issues I'm running into are that upon start up, it immediate by default has RadioButton1 selected thus producing the message that its either correct, if that happens to be the right one, or incorrect. I need to figure out a way top have nothing selected when it runs. Also I have no idea how to disable the RadioButtons like whats asked at the end of the assignment. And finally I dont know how to be able to hint at which ones haven't been selected yet, no idea how to pull that information or how to structure it code wise.

Any assistance in the code for this assignment would be greatly appreciated as Im near the breaking point in figuring out these last few things.

It seems like you haven't paqyed attention in class :p

How can you have no clue as to what to do, wasn't it explained? Weren't you in class? Were you sleeping? :)

I'll give you a hint, for one issue :

Set your tabstop property to false, for all the radio buttons, and then come and tell me what has happened when you ran the form again ;)