There are a number of issues of which this is the first one that needs to be fixed
interface Serial0/0/1
ip address 200.100.20.10 255.255.255.252
interface Serial0/3/0
ip address 200.100.20.5 255.255.255.252
If these interfaces are supposed to connect then they need to be in the same subnet.
Also what is the relationship between these networks
interface FastEthernet0/0.1
encapsulation dot1Q 1 native
ip address 172.16.10.1 255.255.0.0
interface FastEthernet0/0
ip address 172.16.20.20 255.255.255.0
HTH
Rick
