Convert .ps files to something usable?

Hi. I have some (around 300) old .ps (Postscript?) files created by screenshotting a technical program running on an old iMac / OS9. They are diagrams that I'd like to be able to print and share. Is there anything out there that can convert .ps to .jpg / .pdf / .png, etc. I don't particularly want to have to subscribe tto anything on a monthly basis - it's hopefulyl a one-time dealio. Thanks, John