Are those Steam games? When I bought my new Windows PC, I just installed Steam, copied over the old Steam folder to the new PC, then let it fix up any problems itself. It auto-installed any relevant odds and ends (e.g. DirectX updates) the first time I ran each game.
That and 'My Documents' accounted for about 90% of the stuff I had on the old machine.
Non-Steam games dump a lot of stuff in the registry and install DLLs in random places, so that usually doesn't work.