win 95 install with bootdisk

hello-
have an old dell laptop i would like to install win95 onto hard drive. have
reformatted, and started up with boot disk, and have trouble getting cdrom
drive to install. laptop is a dell latitude with switchable disk and cdrom
modules. when using module for a disk drive it can not find the cdrom
obviously, because i can only hook up one at a time. have tried all 4 rom
drive choice options when using boot disk i have win95 cd. i d/l diag.exe
from bootdisk website, but when i run that command in dos the reply is
"cannot locate windows directory".
also d/l ultimate boot disk from same site and when trying to run that in
dos it says it cant be run in dos?!!
what could i try next.
thanks in advance for any direction offered.
peter