I don't think there's such a thing, really.
If you really want speed, reformat the HD so that you can have a data partition and an OS partition. Install nearly everything to the data partition, and keep it as clean and clutter-free as you can. Reformat and reinstall everything on the OS partition regularly, keeping your data intact.
Get a decent AV (just about anything'll do-- actually, what do people think about AVG vs Avast!?) and keep up with the security updates. That's all I can think of, really.