I'd largely forgotten about Mandrake/Mandriva, did they offer a live environment with installer as a GUI application? I'd tried to install Mandrake probably closer to the year 2000 and it certainly did not, but, there's a 4 year gap there that's a blind spot for me pre-Ubuntu.
Never messed with Corel as it wasn't around long, so can't speak for that one.
Focusing more on say, 2005ish, can you think of other examples?
I think we'd have to dig old isos to check but livecds were all the rage in that era.
Knoppix kind of led the way in 2000 so it is not surprising that Mandrake didn't have one yet but 5 years later it was already much more common. Some had separate isos for live or install though.
What Mandrake/Mandriva fell massively was in the branding department. All that mage related imagery made it look like a product for young kids and I am pretty sure that distro wasn't really taken seriously for this very reason.
Never messed with Corel as it wasn't around long, so can't speak for that one.
Focusing more on say, 2005ish, can you think of other examples?