While it would be helpful to know what you were actually planning on doing with these knives (form follows function, after all) for a general "battery" of knives that would fill your needs in a cross country jaunt, I'd choose a Gerber multi-tool with whatever tools you find most useful (MUST have a file, though, and the saw is good to have; the Gerber saw uses jigsaw blades, and are replaceable, so you can have metal and plastic cutting blades as well as wood). The knife blade on the Gerber is okay, but not the best, but you'll have other knives for pure cutting chores.
For a folder, go with a tactical folder of some typs, so that you can have a discrete piece of self-protecion on you at all times. There are tons of good choices out there, so it's hard to say which one is "perfect". Get something with at least a 3.5 to 5 inch blade, though. I have a CS Voyager, extra large (5 inch) clip point plaing edge; good for defense as well as utility. I'm alos looking to get myself a BM 720 with the Axis lock; that is a *smooth* knife.
Neck knife, I guess this depends on if you want it concealed or out in the open. A good open-carry neck knife would be ANY Mora, but my favorite is the Mora 2000. For a concealed, go with the Cuda Arclite. It seems like everybody likes these things, and for $20.00, how wrong could you go? I carry a REKAT Utlity Knife, but they're getting harder to find, and are more expensive than the Arclite. Great knife, though.
Fixed blade, again is this for emergency camping chores or carry on the mean streets? For a good, general purpose camping/survival knife, I went with the BK&T Campanion. Tough, great steel and handle, and will do the work of a knife MUCH larger. For concealed carry, I would love to have the CQB2 Cuda Junior. About a 5 inch blade of ATS-34, great sheath for multiple carry options, micarta handle, and only costs $90.00 for a knife that could be a general purpose tool or a good fighter, should the need arise.
) over all the suggested knives.