There are several factor that make Photoshop takes a very long time to open your PSD or any other related files. Sometime your Photohshop will not responding, hang or freeze. This problem not only occur for a low spec PC but also could happen to a high end PC.
What you need to do is to change your printer preferences.
Use local printer as a default printer, and do not use a network printer. Beside that you can also delete your network printer instead of setting the local printer as default.
Re-install and Update Your Printer.
Sometimes the problem is your printer software is outdated and need to be updated with the latest software. Your printer driver could be corrupted so re-installing could help to solve the problem.
Fix corrupted PSD file
Download the recovery tool from here for both windows and Mac OS: http://www.telegraphics.com.au/sw/product/PSDRecover
This plugin lets you grab image layers from any PSD/PSB file. It's faster than opening the whole PSD in Photoshop, if you just want a layer. Most importantly, it can usually recover image layers from corrupted PSD files that Photoshop won't even open (if Photoshop opens with damage, this plugin recovers a more intact image).
Other basic Diagnosis
First thing fist, basically we just need to close Photoshop and reboot. Next is to uninstall and re-install which is the best way to reset your Photoshop Program. Make sure your system is not overload with many program which will used up your RAM usage. Close any unwanted application.