I really didn't got why you tried to run the X server... weren't already on the graphical interface (KDE, GNOME, or anyone else) and just using a terminal? after the MAKE's shouldn't you do something like make xconfig ou make menuconfig (or even make oldconfig)? if you were in a terminal (like CTRL+ALT+F1) you should just press CTRL+ALT+F7, this will take you to the X server. If what you said mean that you ran all the commands through the Konsole window then you should just step next instead of typing startx (this is my first guess). Any doubts, go ahead and ask. Here to help.

I dunno. I logged in, clicked on Kconsole on the panel and I am running everything from inside the kernel. In the end I didn't run startx as I found in another kernel howto there is no need to run startx - I just went straight to make xconfig
How do I find out the run-level?

Sorry Frandalla,
I didn't notice there was a second page in the previous post. I was following the tldp "kernel mini how to" instructions to the command, which is why I used xstart. I was in KDE running Kconsole. In the end, I decided to skip that command and follow the mandrake instructions you mentioned. After your instructions posted in LQ, I did the following;
make xconfig
edited makefile to set
make dep EXTRAVERSION = -stock (as in stock kernel)
make clean bzImage modules
make modules_install install
Although, mandrake recommended copying/renaming files as well as editing etc/lilio.conf I discovered this was not necessary as it seems to be part of the compile process i.e. lilo had the new kernel added as an option in lilo. Although lilo came up when I selected "linux" and "2422-stock" I got the same problem - blank screen. Through lilo, I can still boot into Windows and linux via "failsafe". I get an error mounting the filesystem, fstab and snd but I still boot into KDE. In KDE I get a big error relating to a sound server.
I thought you could pick the kernels to boot i.e. my old "linux" should still work? The only thing that seemed suspicious was a vmlinux file in the /boot directory in addition to vmlinux-2.4.21-13mdk and vmlinux-2.4.22-stock. Of course, I could have also gone wrong in "make xconfig" as I never expected such a _hugh_ list of choices and maybe by not copying those files caused a problem.
I was upgrading to 2.4.22 to get new drivers and new features (hot plug, IEEE1394, pcmcia kernal, webcam), but instead I discovered most of these features were of the expermential nature so this could also be a reason for the failure. I'll do it again in the next few days, but this time I won't select the expermential stuff. I was described to discover NTFS write was expermential as I have used this in the past with MDK 9.1. to resize my hard drive to configure a dual boot setup!!

hey... about sound that's just because this new kernel is handling the sound modules in a new way.... I'm sorry but I didn't figured how things work, so when I get an answer I'll be sure to keep you informed

Didn't noticed about that but if you want to restore your system back to normal just make vmlinuz point to your old kernel (vmlinuz-mdk_something_you_said_above) and type lilo
that will make your system load the old kernel

the make install step doesn't work (not in mandrake). It inevitably messes up lilo.conf in a way that you won't notice when you just run lilo. The best is to let it do its thing with lilo.conf, and then to manually edit the whole thing again and run lilo (/sbin/lilo -v).