Hi mdoohan,
1) As Bob said, there are several threads on the forum regarding this, I've had some success using the fpdf library (a pure-php library for generating simpler pdf-documents), available at
http://www.fpdf.orgI'm not sure if I've got any code/examples still lying around, but the docs on the site are decent.
2) This is very system-dependant. On a Windows-based system, there's the printer_* set of functions that allows you to interact with any printer available on the system (obviously depending on user privileges).
On a Unix/Linux/BSD-based system, your best bet would be the lpr executable. This would tough require that the lpr executable is available using the exec(), shell_exec(), or system() commands, further depending on any PHP safe_mode settings. Further, you would most likely have to use ghostscript to convert the pdf-document to ps (PostScript), although some system-setups may support such conversions "on-the-fly". I had something similar working on a homebrew'd CMS back in 2002 or so, so given the proper server setup it's fully possible - but may take some tweaking to get it working..
/Fredrik