first point:
you need kind of "static DNS for dynamical IP". Check [1], [2],[3] and [4].
Alternatively, your dad could call you and you tell him the actual IP number.
Or you publish it somewhere on the web, where he can read it.

second point:
make sure that your router forwards the incoming traffic on port 21 to the
correct host (192.168.0.5 ?). Eg in the SUA settings for simpler modes.
also check your firewall/packetfilter settings on ther router/server.

third point:
ftp server: check [5]

fourth point: i don't get
dreadbeast> I've also allowed all permissions to "everyone"
where, what do you mean? your local file system settings?

fifth point: why not using ssh/sftp[6] ?

sixth point: we might have to discuss in more detail some "security issues" here.

cheers


[1] http://dns2go.deerfield.com/
[2] http://www.technopagan.org/dynamic/
[3] http://www.no-ip.com/
[4] http://www.dyndns.org/
[5] e.g. http://www.zdnet.de/downloads/prg/7/...058374-wc.html
[6] http://www.openssh.com/