Silent Hunter III question

Hi all, Im quite new to these forums and plan on purchasing Silent Hunter 3, 4 (Gold) and 5 here soon. My computer in its current state would have problems running 5 at high graphics so for now Im going to stick to 3 and possibly 4 if my comp can handle it.

I have a few questions about 3 for you all however.

First; Can the game actually look pretty dang good with graphics all up and mods? Ive seen quite a few pictures of 3 and it looks good but not too impressive, however, Im owing it to the fact that pictures in many cases do not do th game justice

Second; After looking at amazon, it says this game can only run on XP? I have windows 7 atm, and am wondering if it would run on 7

Third; What are Mods that you guys reccomend, as far as realism adding effects, eye candy (weather effects, some uboat skins as well) anda anything that would affect playability (UI's and stuff like that)

And fourth, how can I edit my emblem on my conning tower, I definately want to have my own 'thing' going on with my sub so that when I surface do deliver the coup'e de grace on a lonely merchant, they know exactly who it is that just sunk them

Oh and please if possible add a short description of each mod they post as well as if I need to get earlier versions and what not.
Thanks all!