I just played around with MenuetOS last night under VirtualBox. It would run fine for about a minute and then the mouse would go crazy (anything I did made it go right) and the whole OS became slower. (memory leak?)
I think there are other programs available for it if you download the CD (perhaps even a web browser) but I never got that far. I find their website very confusing. It seems they want you to use 64-bit only. Unfortunately, my version of VirtualBox can't run 64-bit guests (the new one does, but I'm not about to mess with it). No way am I loading an alpha OS on my main box to run 64-bit. Besides, my machine doesn't even have a floppy drive.