What settings do I use?

You can't do much wrong with the HF100 just make sure it's in FXP High Quality mode. If you want to shoot interlaced and you want to be on the safe side the "Easy" button isn't a bad idea.

If you're concerned of best possible motion capture of fast moving objects you may want to use 50i. I use PF25 exclusively and set the shutter speed in Tv mode to 1/50s because higher shutter speeds tend to show stuttering motion. Slower shutter speeds don't work well when the camcorder is handheld. It's the same as with photo cameras if the shutter speed gets too low you have to use a tripod.

At the moment I'm experimenting with Cinemode which looks promising. Here are some comments about this mode from different web forums:

"Cine mode uses a low contrast gamma - it gives more detail in shadows and highlights, creating a flatter looking image."

"Cinemode attempts to keep the shutter speed at 1/48 (NTSC) or 1/50 (PAL). If there's either too little or too much light to compensate with aperture, the shutter speed will be automatically adjusted. In very low light situations, some gain is applied too, but it tops out at 9dB."

"There's no manual control over shutter speed in cine mode."

"Cine mode turns off in-camera sharpening, so the resulting images are softer than with other modes. Generally, this is a good thing, because there are no halos caused by sharpening around edges. Most of the apparent sharpness can be applied back by sharpening in the edit, but unfortunately it also causes some real, unreversable loss in low contrast detail."

"The Cine mode on the HV30 matches the Canon XL A1's Cine V mode (Custom Preset #8)."

"The parameters of the Cine V preset are Gamma: Cine 1, Knee: Low, Black: Stretch, Sharpness: -4, Color Matrix: Cine 1, Color Gain: -20, Color Phase: +5, Red-Blue: -5, Green-Red: -5, Blue-Red: +5, and Red-Green: +12."

My experience with Cinemode so far is that in good light and with some contrast enhancement (and/or color correction) on the computer Cinemode gives very good results. It keeps gain low, stays around 1/50 shutter speed and rather opens the aperture to compensate for low light than increasing the gain. But again it needs enough light. You don't want this mode to go below 1/50s unless you shoot from a tripod.

Whatever you choose test it carefully first!