If I understand correctly, there are plenty of ACS/OpenACS developers using a variety of Linux distributions, including Red Hat, SuSE, and Debian, so assuming that you have a reasonable grasp of a Unix-like operating system, you shouldn't have much problem. The choice of OS/distribution mostly impacts the initial installation since most of the learning comes from the OpenACS toolkit, Tcl and some sort of SQL (Oracle or PostgreSQL).
Historically, Red Hat Linux was recommended for ArsDigita's Classic ACS-Tcl because Oracle Corporation qualified the Oracle8 RDBMS on the Red Hat distribution first. Installing Oracle (for Classic ACS-Tcl) was by far the hardest part of building an database-backed ACS web server, mostly because Oracle installation tools were buggy and generally sucked. Times have changed though for the better.
Installing Classic ACS/OpenACS isn't the Macintosh-style "Click the Continue button to continue" installation experience, but if you've been using *nix for a while, this shouldn't discourage you. Again, if you're comfortable in your Linux distribution and you're conscientious and careful at editing the configuration files, the installation of OpenACS should go relatively smoothly.
If there are SuSE-specific differences in the installation process, you might try a quick search on this bboard and maybe Google and hope that someone published a little laundry list of idiosyncracies to the web.
I'm sorry I can't answer your questions concerning communityzero since I've never heard of it until today. Hopefully someone else will address those topics.
