I prefer open source software. It’s free. Here is a list of software to avoid if you want the most flexibility and economy. If you have to use it. Please consider running a M$ Windows Virtual Machine that serves it using RemoteApp.
Proprietary software that does not play nicely with native Ubuntu Linux.
Adobe Acrobat Reader
Quickbooks 2016 (Quickbooks Online version is fine)
rClient database software
Silverlight
Giftworks database software.
Martin dean essential forms
Microsoft Office 2016 (Online Office 365 is fine)
Many phone conference web apps!