Hi,
I just want to point out that these emulated games aren't very video-resource demanding, so unless you have an old Pentium 3, then usually you won't have to worry about settings. The best advice: try each blitter and use the one that seems to work the best with your system. I have an old WinXP machine, so I use the "Enhanced" Direct3D 7 blitter.
Some things that are handy to have enabled, under the Video tab: Triple buffering for fullscreen, Win7 DWM Fix, & Rotate vertically Aligned games. As for effects, I just use Scanlines to give a pseudo-crt effect. but this is optional and a personal preference.
best regards,
- dink