All of the non-existent symbol messages might be because it is using a config file (probably from your current kernel 2.6.8) that is not for the same kernel version that you are compiling (2.6.13). But usually this doesn't happen when you are moving to a newer kernel version. Is that all of the output that you get? No other errors?
You need to have ncurses installed to use menuconfig so make sure you have that. But I would think you would get an error if you didn't have it.
Also another minor thing. Normally you want to create a soft link to the kernel source like this:
Code:
cd /usr/src
ln -s /usr/src/linux-2.6.13 linux
that way apps that need to find the kernel source can just go to /usr/src/linux
You can then cd to /usr/src/linux and do make menuconfig as before
Did you get the kernel source from apt? I don't think 2.6.13 is in there yet. It is a good idea to always use the kernel source available in apt because it has some debian specific stuff in there. You can get linux-source-2.6.12 in the unstable branch.