Did you try compiling a new kernel to see if that's the problem? If you aren't familiar with that process, you can apt-get install kernel-image-2.6.5-(your arch) and edit /etc/lilo.conf and update the bootblock file using dd. That would install debian's precompiled kernel, but it may not be optimized. Debian does go thru the effort to make sure it shouldn't give you any problems, and it's generally better this way than having to reinstall linux. (Btw, my first reaction when i ran into problems was to blow away linux and reinstall it, did that about 5 times before I finally quit doing that and started looking for solutions without having to resort to that.) The filemap error you got was the result of a corrupted or tainted kernel. That's why I suggested compiling a new one (kind of hard without an install to do it from but not impossible if you booted from the cd and chrooted to the install and compiled that way.)