UNCTUOUS:
If by "interfacing" you mean "connecting" the wireless and wired networks it shouldn't be too much of a problem - plug the wireless AP into the wired network, and away you go.
If however you mean "I want to see all machines in the network, whether wired or wireless, in windows Explorer" then ensuring the AP bridges properly, and the switch does the same, should do the trick since Windows is pretty promiscuous in its browsing habits.
One other possibility (unlikely since using IP addresses you get connected) is that personal firewalls on the PCs involved may be interfering with the network traffic required to ensure each computer knows about the others.