OK. Here is the scoop. After updating to OS 10.6.4 via DVD. i used software update to get to 10.6.8. That included updated HP printer drivers, but still could not print.
I update the firmware in the printer itself to the latest and greatest from HP. Still no go. Note - HP does NOT have software drivers on it's site for the HP2430N - only the firmware update.
Because my OS is new, I figured Apple should help. I called Apple. The assistant directed me to the HP site update. I told him that the update he pointed me to was a fitmware update, not a driver and that I had already done that.
The assistant had me delete the printer so we could add it back. the only problem saw that once deleted, it did not reappear in the add printer list.
The HP2430N is a network printer - connected to the mac and the other macs around via ethernet through a router - hardwired, not wifi. After a little research, the assistant finds out and tells me t6hat apple NO LONGER SUPPORTS NETWORK PRINTERS!
The assistand had me cycle the router. no luck - the printer did not appear in the add list.
The assistant said that if I could connect the printer directly via USB we may be able to configure it and then get it back on the network configured and working with the new OS.
I connected the prointer directly with a USB cable and the OS saw it right away. I configured and printed. I disconnected the cable and the printer disappeared. The ethernet connection was active the whole time.
BUT, after cycling the router, the printer did now appear in the add list. I selected and configured and now it prints. I deleted the USB version of the printer from the list.
The solution for NETWORK printers boiled down:
connect printer DIRECTLY (via USB), select and configure.
cycle router and disconnect direct connection
make network connections
re-select printer in add window, configure.
delete USB version of printer from list.
My thanks to those who offered to help