1) depending on whether he would like onboard video, the ASUS CUSL2(with onboard VGA) or ASUS CUSL2-C(without). the CUSL2 uses the i815E chipset, while the CUSL2-C uses the i815EP chipset, the main difference being the onboard VGA.
2) MSI 815 Pro, 815E Pro, or 815EP Pro-R. the different i815 chipsets used by each mobo is self-explanatory through the name of each board.
3) Abit SA6R, which uses the i815E chipset.
personally i prefer either the CULS2 or the CUSL2-C. i have the CUSL2 and would have gone with the CUSL2-C (since i have no use for the onboard VGA), but it wasnt out until months after i purchased the CUSL2. MSI's 815 mobos are highly reputable just like ASUS, and the only reason i prefer ASUS over MSI is for the OCing features. but since your friend doesnt plan on OCing, either of the ASUS mobos or MSI mobos would be best. they both have great quality, reliability, and stability. i'll let it be known that, according to AnandTech's tests, the CUSL2(-C) is the only board(s) that can run all three DIMMs cas 2-2-2 @ 133 mHz without sacrificing stability.
Abit seems to have a very nice board, although i have no experience with Abit boards. of all the mobos i mentioned, i think the Abit SA6R was meant mostly to be OCed, though i do not think it is the best OCer by any means. i also have heard many "not so good" things about Abit's product support and policy, and as far as stability goes, i would go with an ASUS or MSI board b4 i went with an Abit.