I have a network (NETWORK B) behind a private network (NETWORK A) which I would like to access fully.
How do you do this on a 2850?

NETWORK A
WAN IP = 23.23.*.* <<<< access to internet
LAN IP 10.1.1.1/24

NETWORK B
WAN IP = 10.1.1.2 <<<< access to NETWORK A
LAN IP = 192.168.1.1/24

How do I access anything on the 192.168.1.0/24 (NETWORK B) network from the 10.1.1.0/24 (NETWORK A) network? I want to access all eg TCP, UDP, ICMP etc but can't seem to get it to run.

Are they VLANs?
If thet are then just enable the inter VLAN routing.
Otherwise you need to do Static routs on the routers to make each interface aware on the LANS

what static routes would I put in?