Whose virtualization software should I start with? Have a couple things I’d like to do in that space.
I'll suggest VirtualBox. It's free, reasonably easy to use, and IMO fairly intuitive for the person who is new to virtualization.
There are non-free packages such as VMware Workstation/Fusion, but there's a caveat with VMware, which is that it was bought by Broadcom recently and the future of those personal-use products is not clear.
Those are the two options I'm familiar with; there are others depending on your platform (OS), such as Xen and Parallels.
However, the caveat about Broadcom applies even more to those offerings.