Please try Sharepoint Designer menu :
Site > Administration > backup website / restore website

The only way that's possible is to backup and restore the whole site. Today,
there is no way to copy  a workflow  from one site to another... it's fixed to the
list that it was created  for.

With that being said, SharePoint Designer creates the underlying XOML file that
defines the workflow behind the scenes. You could copy this file from one server
to another but you'd have to make changes to the XOML file... and there's no
export/import process in SharePoint Designer. I expect we'll see someone in the
community create a open source solution that will let you export a SharePoint
Designer-created workflow -> VS 2005 workflow which is templated and can be
assigned to multiple lists in different sites & servers.

SPD is for creating workflow  for just one list. If you need a workflow for
multiple situations, VS.NET is the correct tool to use.

That said, the SPD workflow designer  is simply generating XOML (a subset of XAML
believe it or not). So, while I haven't tried this yet, coping the XOML text
from one list's SPD workflow to another list's SPD workflow should generate an
identical set of actions and conditions.

In fact, I believe that we should be able to generate some XOML in SPD and then
port that to VS.NET as the starting place for a Workflow Template. If I only had
an afternoon to play with this...

I've had some success in copying *basic* SPD workflows  between
lists. I found I had to copy  both the xoml and xoml.rules files,
and then, as expected, reattach the workflow  to a destination list,
that is, if the workflow had been attached to 'list A' on the
source, you'd need to open the xoml file once you'd copied it and
attach it to a new list.

The problem came about when I'd created  a custom task form on the
source workflow to retrieve user feedback. I found I had to
recreate that form on the destination list.

Saving the list as a template failed to include the SPD workflow.