Clem:

the 90mm, 75mm and 65mm 4X5 lenses coorespond roughly to 28mm, 24mm and 20mm in 35mm. The 90mm will give the most movements (swings and tilts), 75 and 65 less. As to your distortion question, each lens will have some distrotion, some of which can be corrected with camera movements. Remember, there are very few straigt lines in nature.

As Mark said get one lens and get to know it well before looking for a bagful. My first was a Schneider 90/f8. Great lens. I had it for a year before I bought a 210/f5.6