Adding Network Printer - seems to work but doesn't

I have a Dell Inspiron 9300 with Vista Beta 2 Build 5384.
I am trying to print to either a Samsung SCX-4016 or an Epson Photo R200.
The Samsung's driver is not in Vista but I was able to install the XP
driver.
The Epson's driver is in Vista.

I have the two printers connected to an XP Home machine (Machines 6212).
They are shared correctly because I am able to print from my Dell when XP
and Bantu Linux are installed.

In Vista, when I try to print, it claims to be sending the print job to the
printer and acts like it all worked fine on my end.
But nothing happens.

I tried some of the helpful things here but nothing works.

Any ideas?