Linksys - Create Private And Guest Network?

I wish to establish a private and guest network for a local business. They have Verizon service with its wireless router plus their own personal wireless router.The Actiontec mi424wr (rev i) wireless router is connected via Coax and will remain the first in line so as not to disrupt the set top boxes (STB) channel guide and other features managed by the Actiontec. The radio is active with an SSID of "ABC-Private" and its network is 192.168.1.xx. The thought is that only business personnel will connect to this router for internet.I have connected their Linksys WRT54GS to the LAN port of the Actiontec, using a static IP which I have allocated in the Actiontec's DHCP pool for this purpose. This radio is active with an SSID of "ABC-Guests" and its network is 192.168.2.xx. The thought is that only patrons will connect to this router for internet.

My overall goal is that business personnel will have unrestricted access to the internet AND to each other¦ while patrons will only have HTTP and HTTPS access to the internet¦ and no communications will be permitted between the two network subnets. I realize there are hardware firewalls designed for accomplishing such a goal, but the business hopes to avoid the additional expense, if the aforementioned model can provide this capability.In order to accomplish this goal, my remaining tasks as are follows:

1. On the Linksys, permit only http and https traffic (and whatever else the patrons would need/want).

2. On the Actiontec, deny Linksys IP address access to everything except for the Actiontec gateway.