General Questions

WAN:

In/out packets    511928/478204 (305.21 MB/72.75 MB)
In/out errors    0/43
Collisions    0

LAN:

In/out packets    475760/494905 (69.34 MB/299.69 MB)
In/out errors    0/0
Collisions    0

Does this mean (305.21-69.34)M has been blocked from outside and also (299.69 - 72.75) has either been blocked from inside or just purely intranet traffic?

Your m0n0wall also acts as a router, so normally what comes in on WAN goes out on LAN, and vice versa. Thus, "only" a couple of MBs have been blocked, which is quite normal.

Also note that the counters are 32-bit, so they'll overflow at 4 GB (leading to funny looking values after the firewall has been up for a while).