Yes you can save specific settings to the "C" mode on the dial. You can save P, TV, AV, M...I think that covers it. You just set up the mode like you want to save it, then do Menu->Save Settings (I think it's the bottom menu item) and then when you switch to C mode all you stuff you saved including the mode will pop up.
C mode works differently than the other modes - you can change what you want, but if you turn the camera off and then on (or switch modes), unlike the other modes, it will forget your changed settings and go back to the settings you set when you did Menu->Save Settings.
On mine, I have C set to the following -
P mode
Flash - On
Iso - 80
AF Frame - Face AiAF (it's the first item under Menu, it helps keeps peoples faces from getting blown out by the flash)
Not that all these settings would necessarily help with your fish pics though. I mean - iso80 results in a sharper, cleaner picture - but it also results in a dark background, and more importantly turns up the flash power so it's just going to make the amount of flash shown on the fish higher.
There's 2 ways to get the flash power lower -
1. Use a higher iso (but then the pic ends up noisier and less clean)
2. Use a longer shutter speed...if the camera is on a tripod that's ok for the camera, but it depends on how steady you can stay yourself, and whether the fish moves.
If you want to eliminate the flash reflection, that done by "bouncing" the flash or by using an external flash and a flash umbrella - unfortunately I doubt either of these techniques would be useful for you. You can use a sort of external flash and bounce it on the s95 -
http://forums.dpreview.com …age=36183658&changemode=1
But you need one of two things -
1. A large white surface nearby to bounce it off of. Indoors a lot of times a wall or ceiling does this...outdoors it seems highly unlikely something like this will be around.
2. Or bring your own large white surface - a flash umbrella. However, if you want to save time I don't think setting one of those up will be within your time/hassle limits.
To be honest I think the picture you have above is pretty decent. 