You're damned if you do, and you're damned if you don't. But it's typically better to "do".
I have been working in WordPress support and development for a number of years now - and I can certainly say it's much better to keep everything up to date.
Wait a little bit (2 weeks or so) after major updates before making the change to allow time for maintenance updates to drop in case something was badly broken by the major release.
Most developers work hard to ensure backwards compatibility and with WooCommerce's glob of add-ons and millions of users I'm sure it's even more so the case there.
Yes, stuff can break, but you can't always know or even anticipate what. So be sure to read the changelogs, signup for newsletters, and follow the blogs of the most critical plugins running on your site (like WooCommerce). Stay in the loop, and there will be less surprises.
But in the case that something does get badly broken, you have a few options:
Backup, backup, backup - before doing updates. Plugins like
BackupBuddy, or VaultPress that automate the backup/restore process
are definitely worth the effort or price in my opinion. Your backup
should be sufficient, but may be harder to restore.
Hire a developer from a site like http://wpfixit.com/
Fight to fix the issue yourself (not recommended, especially if
you're not techy)
As for your questions, it's difficult to answer as there are so many variables. There's no way for me to know if you'll be safe updating or not. But if you have a reliable backup system in place that makes restores easy to run, then you can have some confidence in that before pulling the trigger.
Lastly, I'd consider creating a staging site that mirrors your live site, where you can test updates before doing it on your actual live site.
