Paranoid about my saves.

[LTD1]

Hello one and all. Looks like there is an utterly amazing community floating around SHIII! Some of the mods people here have created over the years are beyond incredible!

Shame the stock SHIII has it's fair share of minor oddities. Such as rather irrational way it handles saved games. I can live with "load this game and everything beyond is destroyed!" just fine.
"Delete this game and everything beyond it is destroyed" caught me off guard. Apparently safe amount of other overall Fubarness exists.

Er so! long story not short enough, which files do i have to copy if I wish to create a backup of a saved game? Is it possible in first place? If so, does manually restoring a saved game in that way increase risk of instability in some way?
Any other tips or suggestions how to ensure I don't get any nasty surprises some 20 patrols from now?

Other random inquiries:
Are there any finished Mods out there that enable me to walk around freely in my precious sub?
..Or mods(beyond the lovely SH3 Commander) that somehow make "my character" more present in game?Ie add him among the crew of the ship and whatnot.