Windows 98 really needs 32MB to be of much use, and is still liable to be swappy unless you have more. And while it supports 486 CPUs, the IE integration is heavy and it runs better on a Pentium. You could Nlite Windows 98, but stomping on the OS like that can and does create compatibility issues, especially if you do an aggressive Nlite that actually makes 98 run as fast as 95. I don't think 98 makes much sense anyway, because most software which has any business running on a 486 or early Pentium supports Windows 95. And the newer the OS you pick, the more likely early Windows software that targeted Windows 3.1 and 95 RTM is to break.