restore macbook to original factory settings

I had a super old version of snow leopard so bought the version 10.6.3 to upgrade. I tried to follow diNicola's instructions, as it seems a lot of people were having success with that, but after installing the new OS, it just brought me to my regular welcome page, with no recovery option. I tried Command+R while restarting and that didn't seem to work either. Sorry for being a dunce, but how do I delete the existing accounts and create a new blank admin account?

Thank you!

Oh, also, it is an OLD Macbook- maybe 2003 or something? I was hoping to clean it up and sell it for just a couple of bucks- It looks like it is no longer possible to upgrade from Snow Leopard to Lion? Also, the new Snow Leopard version is now stuck in the disk drive :/

Kappy, These Apple's do not come withe any DISC just a charger .

This fix works perfectly. It was easy and my poor old macbook is clean as a whistle and working better than ever! Thanks DiNicola 🙂

Thanks for your reply, when I power on and presss option key, what I saw next was Macintosh HD only no Recovery.

Any idea what to do next?

Thanks