The owner and computer name of the workspace are not editable in Visual Studio 2010. However, you might need it when you renamed your machine or your account is renamed. To do this, open a Visual Studio Command Prompt (2010) from program files, and cd to your workspace, then run following

Change the computer name for a workspace

tf workspaces /updateComputerName:<OldComputerName> /collection:<CollectionURL>

You need replace <OldComputerName> to your actual old computer name and <CollectionURL> to your actual TFS collection URL.

Change the owner for a workspace

tf workspaces /updateUserName:<OldUserName> /collection:<CollectionURL>