[Grml] kernel panic and slow start up

I've installed grml on a usb hard drive, and had success (except for it spending a lot - 10 minutes at least - of time "Loading kernel 2.6.16" if I remember the message properly).

But after I did: apt-get update apt-get upgrade (which had some problems so I did apt-get -f install)

I get a kernel panic during start up, it tells me to set the proper root when I start, or something like that.

I suppose the first thing is how to resolve the kernel panic (I'm pretty sure that without doing a dist-upgrade my kernel shouldn't have been touched).

If I can get that resolved, I'd like to know why my computer can boot faster from the CD than from the hard drive (it is a USB2 connection).