Depends on what they do about shaders, in Arma1 you could turn off normal and specular maps but Arma2 you cannot. Furthermore you can push very high detail on even the lowest computer, but you generally have to sacrifice view distance.
@ OP, the problem is that chances are your friends would drop the game anyway, if graphics are their primary concern then I have little to no doubt that the complexity would drive them away in the end. While the graphics can be pretty, beautiful even, and a great deal of the game, they are not the core, and the core is what drives most away regardless of any imagery.
It's like comparing old classics such as Janes Fleet Command, Fighting Falcon, Janes Longbow and so on, the graphics may not be great by todays standards but it is not the graphics to which we stake everything on. Even todays great DCS black shark is pretty simple in terms of "Graphics", the only real beauty's you'd see would be the aircraft, the rest of it is simple in clutter, very little in shaders and so on. If you have any of these then show it your friends and get thier opinion, if they cannot bare to play them because of the graphics then chances are, it's not for them.