System Rescue CD, which is what I always use.
I've had some good luck over the years with all 4 of those. And there's another one that I can't remember the name of right now to save my life. It's a paid program. I bought it probably 15 years ago, from a German company. The disk it was on got melted a few years back and I haven't been able to find it again. It was from a small company, they may have been bought up or gone out of business. But it was worth every penny. I was hacking one of my drives about 10 years ago and flubbed up big time and blew up all of the partitions on the drive (doze). I pulled out that disk and recovered all but about 2% of my data.
If you are worried about other people seeing your data when you sell your machine, why not use one of the Ubuntu "alternative" (or other distros such as fedora) installs that allow you to fully encrypt your disc. That way, when you reformat and reinstall the new OS, nothing can be read from the old data even if it is not overwritten. This also solves the problem if some one steals your laptop or it is lost, as it makes your data unreadable and safe from prying eyes.
I was wondering about D ban (deriks boot and nuke) I like to use that one, but does it delte data or just change it?
as i understand it, DBAN deletes the data and then overwrites the sectors on disk with a method of your selection (Guttman, DoD, etc.), rendering the data extremely hard to recover.