What is the difference between ...
... the Personal and the Corporate versions of Active@ File Recovery?
The difference is in the licensing. You can't use a personal version of Active@ File Recovery for business purposes.
... the File Recovery DEMO and the Commercial versions?
The demo version is a freeware version for evaluation purposes only. It contains all of the features of the commercial version, but has a 64kb limit for the maximum file size that can be recovered. The commercial version of Active@ File Recovery allows for recovery of any sized file.