My site has been made inaccessible!

Since the beginning of February, my site - "7-00-07" - has been inaccessible, except for the fact that I can still access the files and the database through the (free) web hotel (the personnel of which alas hasn't been of too much help).

I get different error messages, depending on the browser I use, eg.
~"The page is wrongly redirected. Firefox has detected that the server is redirecting the request for this site in a way that makes impossible a completion.".

No vital information seems to be lost, however there seems to be some kind of redirecting the server issue (or maybe "sql injection"? ) involved.

Is there any simple way (/software?) to detect corrupt files in a mysql database and repair them?

I've tried to copy the site to a couple of different domains, which works slightly better, at least if I try to load an old backup to "phpMyAdmin" but still far from satisfying.

One major problem seems to be the user file and how to update it (/combine it with an old one) and still be able to log in.

I've also tried to install a newer version - "7-02-06" - on one of the other domains and then copying some of the old files to it and its database but that seems to do more harm than good.

In other words, I'm trying to upgrade the site in an improper way.

For the present, I'm trying once more to upload a clean "7-02-06" version and start all over.
:o .

Thanks to some script I installed, I have some IP logs, from spammers behind VPN tunnels (run by a founder of "the Pirate Bay"(!), who claims to be for ~"free Internet"!).

Maybe those logs would help someone?

I'd be happy to know if anyone else has encountered similar problems.

All this is so frustrating, that it's soon bound to drive me n*ts.
:(

It gives me nightmares, literally speaking.
Thanks beforehand for helping out.
:G