What is a safe way to dispose of personal info on an old laptop and what to do with said laptop?
A "boot and nuke" CD is the way to go, something like http://www.dban.org/ should do the trick. This will allow you to securely and easily wipe the hard drive.
I've donated my obsolete machines to Goodwill. They have an agreement with Dell where the machines are recycled. You could also look for local charities that might have a need for computers, or perhaps your local library.