Is it possible to a full system Copy and run it in Parallels?
I don't have experience with Parallels, but if you own an external hard disk, you could clone your Mac Server to this hard disk (e.g. with Carbon Copy Cloner or also OS X Disk Utility).

Then boot from the external disk and try whatever you want to try/install - it will not affect your Mac's internal disk. So once you disconnect the external disk and boot from your internal disk again, everything will be as it was before.