Getting rid of an old computer

Yes, using something like Boot and Nuke is sufficient. If you're really paranoid then your only other option is physically destroying the hard drive. Boot and Nuke will make any attempts at forensic recovery of files a real pain in the butt.

I actually remove the hard drive before disposing of the rest of the computer, and then keep the hard drive in a cupboard for a year before then disposing of that. Very often people have asked for data from the hard drive after the machine has gone.

"I'd say before wiping it or anything, make sure you can't salvage any of the parts first. U can always turn an old computer into a headless server, or a home theater PC, or something. I mean you'll most likely need to give it some upgrades, but it doesn't need to get thrown away.

If you're getting rid of it though Dban"

If you are planning on recycling them, then I think destroying them (physically) is good enough as long as it's for sure not possible to somehow fix the hard drive.