The first thing you need to do to fix the printing problems is checking the Print Spooler service and drivers.
Firstly go to Start > Run > services.msc and locate Print Spooler in the list. Right click it and choose Restart. Secondly, check the drivers in Device Manager using Start > Run > devmgmt.msc. If there is any driver missing, right click it and choose Update Driver. Let it install automatically then repeat the printing process.
Note: You might have to re-configure the printer for a custom layout, depending on the size of the tickets.
For the PDF part, access its configuration instructions and if you see a button called Default, press it. It will restore all the settings to default, then attempt to open files again.