@Zane: Yep!
Bear in mind you won't save much if any disk space with a clean install, though. In almost all cases we replace "files to delete" with 0-byte empty files to overwrite them. I'm sure there are a few we missed, but we're talking ten or twenty mb at absolute most.
Anyhow, just reinstalling from the 7.0 installer and then the various latest versions of the expansion installers (most do not change over time, so are several years old) will do it.
@solid: If you are an alpha or beta player for votm, then yes. We don't have them yet, though.