I backed up the front page of this site: http://ialc106.ip.wsu.edu/edtech/moodle/
Using the backup file, I restored the front page as a new course in another Moodle on the same server (same Moodle version, 1.8+).
The only content that restored was the course description. Everything else, including wikis, forum entries, and resources, is missing.
I also tried restoring the front page to a new course within the same Moodle and had the same result.