A simple export to a .PST file should capture all items (mail, contacts, calendar, etc) in any Personal Folders. Be certain to check the "Include Subfolders" option.
As far as individual mail account settings are concerned, it is often such an easy task to recreate these that it defeats the purpose to have some sort of backup process. That said, I believe Outlook 98 did offer an option to backup individual mail account settings to an .IAF file.