I am using DotNetNuke 6.2.6 , and recently got stuck in one issue , I do not want my users to receive random password after they reset their password (forgot password), Instead I want to send them password reset link. I could not find any settings under Web.Config or under host settings. I did some research but the articles I found that referred to DNN7 . On DNN website I found only this link http://www.dnnsoftware.com/wiki/page/password-reset-links. Registration mode is verified.
I think that you will need to upgrade to DNN 7 to get this functionality.
Iowa Computer Gurus (iowacomputergurus.com) has a module that provides this functionality if you are not able to upgrade.