[ianc]

I don't really understand what you're trying to accomplish, but:

The route statements work like this - when you enter a route, then you are telling the router to use that route to REACH a destination network. The statement:

ip route 66.236.106.64 255.255.255.224 FastEthernet0/0

Is telling the router that to reach destination subnet 66.236.106.64, it should use int Fe0/0. When the router receives traffic bound for this subnet, it will forward it through Fe0/0. Likewise the other explicit route statement you've entered.

The default route statements are just that. If you don't have traffic bound for either 66.236.106.64 or 67.93.43.160, it will use the serial ints.

Try to explain what you're trying to achieve a little more clearly, in terms of both inbound and outbound traffic.

ianc