Should I enable router mode on each of the wireless routers but give each wireless router a static ip address on the modem?
Will the wireless routers then allocate DHCP for connected devices?
No, set your wireless access points to "access point" mode.
Yes, give them a static IP address.
It depends, on how you configure things. I recommend having your wireless access points "pass-through" DHCP requests to your central box that does DHCP.
The ip camera is showing in the modem DHCP table as 192.168.0.103
That's because the lease hasn't expired yet. Ignore it.