du,df tools

[Brian Henning]

Greetings:
I would like to use df and du tools to get some stat about my files and my disk.

first, why does 59375408 + 1348433 != 61337213
df -k /home/henninb
Filesystem            kbytes    used   avail capacity  Mounted on
                     61337213 59375408 1348433    98%    /home/henninb

second, when i try the following command i get the result in usage on the disk.
does du give results of  'actual file size'? can i get it to report the result
in bytes or megabytes?
du -a -k /home/henninb/

Thanks for any help,

Brian