What is the problem here? What do you mean by "old HBC"?
From what I understand you just don't like the way bootmii boots before the system menu, hence you have the idea of renaming the bootmii folder? Of course this works, if you rename the bootmii folder on your SD card, bootmii won't be able to find the necessary files to run and will start to Wii system menu instead (after flashing DVD leds).
However, there is another solution to the problem which will make bootmii unnoticeable and just boot your Wii directly to the system menu. Just see what I wrote at the
"how to autoboot to the HBC?"-topic, now if you just copy and paste that into your bootmii.ini file, and then change the
AUTOBOOT=HBC to
AUTOBOOT=SYSMENU, your Wii should just boot without showing bootmii.