I have finally managed to install tex, latex, etc on my home computer, and it seemed that my previous problem was caused by a corrupt file during downloading.
Just an observation. It seems the auctex is not setup properly after installation (it could have been caused by the fact that I didn't install emacs-el). The file tex-site.elc is in the directory /usr/emacs/site-lisp/, but that is all. When a tex file is loaded in emacs, auctex functions are not available. I've linked tex-site.elc to site-start.elc for a remedy, but not sure if it'll cause any problem in future updating. Any suggestion?
A separate question: where is the source for the current kernel? I would like to recompile the kernel to get rid of many not needed feature and reduce the image size.