Full Website Backup with Snapshot


I've been testing Snapshot plugin and I've realized it doesn't backup the entire site just wp-content folder and the databse backup is segmented by tables. I've been doing manual backups of my sites (whole installation and sql database) and sometimes I have to restore it all. With Snapshots I don't know if I'll be able to restore the backup if my site breaks entirely and I can't log into wordpress, or if it's accidentally deleted. If I try to restore the snapshop into a fresh wp install with a new install of Snapshot plugin, would it restore the entire old website even though this backup wasn't created with the "new" Snapshot install but with the old one?
Also, I run older wp versions in several websites and snapshot doesn't backup wp files does it? So, if my website is deleted and I need to restore it entirely including old wp version (and I can't remember exactly which version I was using), will I be able to do it using Snapshot?