Very few is the bottom line answer, I would think, without the database.
One possible without an SQL dump and if on a Linux system (below for CentOS system), using a rescue CD to boot server from CD. Allows crawling of what can be seen of the drive, one could possibly copy the DB files located in folder
/var/lib/mysql/[dbformoodle]/
off the failed server and then place them in a [dbformoodle] folder on a new server. Permissions and ownerships would need to be set as the copy/move/xfer may not retain those attributes. Owner/group = mysql and rw for owner/group only. Make sure the MySQL daemon is NOT running on the new server when copying. Start MySQL only AFTER files have been xferred. Further settings to the copied DB would be needed - moodle user that has access etc.
And probably best to check the tables for corruption and repair as soon as one could.
mysqlcheck -u [user] -p[password] --analyze --databases [dbformoodle]
mysqlcheck -u [user] -p[password] --repair [database4moodle] [mdl_table_to_repair]
There is also the moodle code directory at web root. In that folder a version.php file which indicates the version of Moodle. Not sure one could re-acquire the same exact version, but one could get close ... highest version within the series (ie, 1.9, etc.). If one had any add-ons, might want to acquire those and unzip in the proper folder of the code directory first before starting MySQL as well.
Best of luck!
'spirit of sharing', Ken