migration of a 4.1.3 to 5.1 without an operational server

[Murias O'Ceallagh]

I hope that I am able to make this as clear as possible.

I have inherited a serious jar of pickles.

I have a hard drive that has the directory structure of 4 different freebsd machines on it. This drive is nonbootable. From the root of the hard drive looks like this:

/machine1
/machine2
/machine3
/machine4

Where the directory structure below each machine director is an rsync backup of the entire file structure of that machine. such that the machine1 directory does have /bin /usr /boot /root /etc .... sub-directories... and so do the other machine directories.

What I need to do is get all databases out of the machine2 directory which was running MySQL ver 4.1.3 and migrated to another running machine that has 5.1 on it.

What are my options? I am willing to try anything that gives me the end result.

The existing databases on the machine that is running 5.1 are of no consequence to anyone, and can be obliterated if needed.

I greatly appreciate any and all insights that anyone may have for me.
Cheers
Murias