G'day there Lorenzo,
The first line told me that the db was a newer version than the program expected.The db is likely to be corrupted. Try running from command line and post here the fist 10 lines of f-spot output. It will probably say the db version is incorrect for your running version of f-spot.
Anyway, I'd suggest you to move away your photos.db and restart from scratch.
However, removing the database and starting f-spot again fixed the problem :). It's now working like a charm.
Thanks very much for your assistance. I certainly appreciate it!! See ya Thanks again Ken McLennan Qld, Australia