Printing headache

[toyfactory]

Still no joy with the printer.  I'm running a fairly basic Warty (!)
installation.  I have a USB DeskJet 5650, I've installed the driver
using the System Configuration Printing window and successfully printed
a test page.  I can print from GEdit but I can't print from three very
important applications.  I've downloaded the two extra packages from
universe as suggested earlier without success.  Here's what's happening
(or rather not happening):

Printing from Gimp

I load up a picture I want to print and go File, Print... My printer
appears on the Printer Name drop down menu, great.  PostScript Level
2 seems to be the default Printer Model but never mind, I'll try it.
It doesn't work.  The printer prints one page which says something
like "%!PS-Adobe-3. %%BoundingBox Yadda yadda yadda" and then starts
spitting out blank pages until I turn the printer off.  So I try the
Setup Printer... button.  I can't find my printer there so what
should I do?  The print command looks like this: lp -s -dDeskJet-
5650 -oraw and the PPD file I downloaded earlier looks like this:
/home/nick/HP-DeskJet_5650-hpijs.ppd

Printing from Open Office

I go to Open Office Printer Administration.  My printer appears there as
the default printer, the command: lpr, the driver: DeskJet-5650
(CUPS:DeskJet-
5650).  I click Test page, and wait.  The dialog box tells me "The test
page was printed successfully."  Nothing happens.  I try and print a few
times from OO, nothing happens.  I check the print configuration to see
if there are jobs waiting to print.  Nothing.

Printing from Firefox

I click Print.  The only printer on the menu is Postscript/default, that
works - it produces a .ps file.  But I want to print directly to the
printer - how do I add my printer to the Firefox menu?  A little bit of
web searching suggests maybe I need to install Xprint from universe.

Any assistance appreciated,

Nick