lastlog is huge

[david smethurst <davidjs netspace net au>]

hi all 
ive been trying to ghost over my drives from 160gb to a  36gb and
couldnt figure out why it keep saying that the destination drive was too
small.
then i found this:
in /var/log/lastlog is 1168.0GB
its locked of course but please what can i do about this and why is it
so big?
the drive is not big enough for the size so something else is wrong
question? how can i tell how big everything is?
i tried to use the file size view in konqueror and it just keeps locking
up all the time so that i cant use it anymore and go to the home
directory
thanks for any help
david