Downloading of Spider Solitare that comes with Windows is not possible as it's a product bundled with the Windows installation. If you have a Windows installation disk, you can install it from the Add & Remove Windows Components from the Add & Remove Programs in Control Panel, or Turn Windows Feature on or off if you access Programs in a newer version of Windows.
In case you want an alternative, this search query from Software Informer's database lists all the Spider Solitaire products available to date.