Doesn't matter. "Read-only" means that you're only allowed to read the
file, not update it. If you're making a copy you're only going to read
it, so the read-only flag won't hinder you. The "Archive" flag gets
set any time a file is changed, to alert a backup program that this
file has changed since the last backup. That won't bother you if
you're making a copy of it either.

When files are burned to a CD-R, the read-only flag is usually set
since you can only read any files on that disk. When you copy them to
another machine you may need to turn that flag off before you can use
them.