I've now found a much better method. Since Wii Menu version 4 you can now move channels to the SD memory card and load and run them directly from the SD card. The Wii also allows up to 240 channels to be installed onto each memory card, and since Menu 4 it now supports SDHC cards up to 32GB which is more than enough room.
So I've now moved all of my WiiWare and Virtual console games to the SD card and run them from there. Leaving the main Wii channel menus clutter free. Sorted.
Also having support for 32GB cards also makes running ripped games from card more appealing, and I might try this instead of using an external USB HD.