uCLinux footprint breakdown?
Note that uClinux closely related to Linux; kernel-wise, it's just a patch against the standard Linux source tree.

As of version 2.6.26, The patch adds machine support for some of the m68k boards, as well as some changes to a few drivers, relevant to those boards. However, for ARM platforms, the uClinux patch probably won't give you any benefit, as it doesn't touch any ARM code.

So, the figures given for a standard Linux kernel apply to uClinux too.

You'll find exactly the same drivers available as the standard Linux kernel, so you won't need to do any porting.

Bonus bonus answer: if you're not accessing an external storage device (and have your root filesystem built-in to the kernel image), you won't need a filesystem.