Removing Windows but having problems

Hello,

I have been having some problems in getting rid of the windows partition. I want to dedicate my whole Macbook pro back to OS X but I can not figure out how. I have looked on many sites and most say to use Boot Camp or move all my stuff to an external and reformat the hard drive. Well I have been getting an error when trying to use Boot Camp it says that "You must update your system software before using this setup assistant" but I am fully up to date on everything, and I do not have the money to get an external drive. Can anyone help and tell me another way to remove the partition.

Thank you.

 

Thanks but still has the same problem where Boot Camp won't run.

 

No I believe I am using OS X Leopard.