RTM releases or repair discs offering
Don't confuse the "repair OS disc" as a full install. They tend to work on already installed OS, in order to clean or clear some glitch or mishap and allow to reboot properly or similar fashion. Some of the other sources also tend to rely on old OS as if you're updating to the newer OS. The whole being once you get into all this, the chances of working are 50/50, many times these "free or open website OS" aren't made to be full installs. You can still however request as a legal option a "recovery/restore Vista disc" from sources, check link. Also, the other link I provided greatly relied on the "key" to work, so if that is an issue another error in the making. However, it may not simply work because it was pre-release of Vista that was "beta" and is no longer supported.
http:///www.restoredisks.com >>>>> google for others or similar
These are to re considered, OEM type install and are suppose to work only on your model# or series PC. If you haven't yet, Gateway may provide this service also at some low cost. Yeah, your Gateway came with the restore partition on the old HD, BUT you were suppose(allowed) to create restore/recovery discs as part your safe recovery if the need arise besides the HD provided one as well.
As for Digital River source, you may want to contact them to see why the version you got, failed. -OR- query there to see what problems are resolved, being provided by other users or links to such.