Data transfer headaches (continued)

Hi everyone
After problems previously posted here I finally was able to get hold of a 6-pin to 9-pin Firewire cable and am trying to transfer the data from my desktop imac (OS10.5.7, 2 Ghz Intel Core Duo processor, Memory: 1GB 667 MHz DDR2 sDRAMM)
to my new Macbookpro (OS10.5.7, 2.26 GHz Intel Core Duo, 2GB 1067 MHz DDR3)


I started the imac pressing "T" to initiate the transfer, the two macs connected okey, but when the icons for user data, apps and folders came up the total is listed as more than the macbook's capacity - something like minus 16 GB. The user data on my imac is listed as a whopping 127GB.

Why is this? the macbook has more capacity than the imac surely?
Why is my userdata folder so heavy? The only significant weight on there should be my email folder and itunes library. Lately my imac has been running very slow, "sticky" keys etc. I wondered whether maybe someone had hijacked the HD.

I don't know the answer to why your home folder is bigger than your hard drive, but remember that your /Users/you/Library folder contains a lot of stuff. Mine's just under a gigabyte.

Thanks very much! It seems something strange is going on with my hard drive on the imac, possibly data folders have been duplicated, as I had some problems with itunes and email a few months back. After some advice I managed to avoid the issue for my macbook by transfering only the applis, files and data I need on it, but I'm still left with a few question marks over my imac. Sounds like time for a serious clean out!