messed up my system

[revolution_of_1]

hello -
I am new to gnu/linux and have a small problem. I recompiled my kernel but wasn't successful. I downloaded and tried compiling another 2 kernels but no go. My stock Mandrake 9.1 kernel still works. What I would like to do is delete the three failed kernel installs. The installations went fine and the kernels are completely installed. The problems occurred afterwards. I just want to delte them and start over instead of fixing them. I will make do with no sound and the stock kernel for now.
How and what do I need to delete to remove these other kernels? I know there are module folders, src folders, config files and quite a few others that need to go. Each src folder is taking up around 155 megabytes alone. I installed the kernels via rpm on a Mandrake 9.1 system with grub as the bootloader. Any help is greatly appreciated.
Thanks -
revolution_of_one

[Kiamu]

a kernel just installs
- a kernel image (usually vmlinuz in / or /boot)
- System.map ( usually vmlinuz in / or /boot )
- kernel modules (usually in /lib/modules/<kernel-version>/ )

if you can boot your custom kernel leave vmlinuz and System.map in place, because they are the right ones.

you can leave also the kernel modules in place... they only occupy some space.
the most is in the kernel-source-tree. that one can be deleted safely. if you are unsure and your systems runs: leave it as it is, until you are sure what you are doing

[revolution_of_1]

Thanks for quick reply. So there are not a ton of config files I need to worry about causing problems? It sounds to me like I can delte everything that refers to the kernel version numbers I installed. I still am not sure about /usr/src/linux That has been changed to a symbolic link that points to the last kernel I installed. I want to delete that kernel. Should I delete /usr/src/linux also or make it point back to the stock kernel that came with my system? Before I installed these other kernels my /usr/src folder was very clean and tidy and just had a /linux folder in it and a sources folder in it. Now the names of the original kernel have been changed. Should I rename them also?
Thanks for your help and advice. I appreciate it
revolution_of_one

[Kiamu]

Originally posted by revolution_of_1
[..] I still am not sure about /usr/src/linux That has been changed to a symbolic link that points to the last kernel I installed. I want to delete that kernel. Should I delete /usr/src/linux also or make it point back to the stock kernel that came with my system?

make the symlink point to the stock kernel sources. deleting the other kernel sources is save.

Before I installed these other kernels my /usr/src folder was very clean and tidy and just had a /linux folder in it and a sources folder in it. Now the names of the original kernel have been changed. Should I rename them also? [..]

I don't know the structure of Mandrake, but usually the /usr/src tree contains the sources of the kernel + a symlink to the kernel-sources. (could also be that the sources reside just in /usr/src/linux). the symlink to /usr/src/linux is needed by a few packages that compile against the kernel-sources (like alsa for example).
these files (the sources) are not needed for running linux. the only files linux uses from the kernel tree are vmlinuz (the boot image of the kernel) the System.map (tells the kernel for example about modules etc.) and the modules in /lib/modules.