Hello everyone

I am new to the community (FSO) but not new to FS. I have played FS when it originally came out both 1 and 2. I was feeling nostalgic the other day and wanted to test FS2 on Win 7 x64 RC so I wiped off the CD's and installed it. With no issues I simply wanted to update the version and stumbled across this site. Wow am I glad I did. I just installed the FSO 3_6_10 RC2 and my current rig is infinitely better then the old pentium I played the original on so I wanted to maximize the graphics.
My question is in this new launcher there are some options I am confused about to maximize the graphics.
I understand D3D 32 bit mode is unstable? Is there a known reason for this?
What under the graphics settings actually makes it worse? ie "disable motion debris" or "stops fog intersect hull" or how about "use specular alpha for env mapping" listed under experimental.
I am running 1680x1050 32 bit trilinear 16x 16x hi res pack but it doesn't seem that much better if at all then when I played it many years ago. Or do I just have a bad memory? lol
Is 60 fps the max? I never get more or less...
Sorry for all the questions I tired the search but I really couldn't narrow much down.
Cheers!