Since I switched to Snow Leopard I was not satisfied with the printing drivers for my old HP OfficeJet 95. I used the included Gutenprint drivers. For text they worked ok, but images looked terrible.
Today I decided to do something about it. From Linux I know that HPLIP has some pretty good driver (hpijs) for most HP Devices. Fortunately I can use the same drivers for Mac OS X to. You need three packages to do this. More information can be found on the website of the Linux Foundation.
This should help you get your old HP Printer working.