artistic

I'm selling my old PC and I want to get rid of all my personal data so the buyer will have a totally clean computer. My question is, will CCleaner delete past files that I simply deleted with the Recyle Bin or by deleting my internet history prior to getting CCleaner? I would just reformat my hard drive, but the computer didnt come with a Windows CD to do that. Am I on right track by using CCleaner or is there something better for what I want to do?