Nero claims, in its helpfile, that Windows 95 writes
to the Hard drive during the boot process.
If this is the case, what happens when W95 is on a CD,
and can’t be written to during the boot process?
Link.
Only some files are written, such as the pagefile , some registry entries and some .ini files. Not that much.
If you are looking for a way to boot Windows 95 from CDROM instead of harddisk , forget it… it won’t work flawlessly and will require a LOT OF tweaking with ramdrives. (Sorta like Knoppix does).