Hi again,
Take a look here - it explains how to remove the hard drive.
http://support.dell.com/support/edocs/systems/sxl1645/en/sm/hdd.htm#wp1109848
I think the drive will be SATA but take a look here - just to make sure.
http://kenspchelp.co.uk/viewtopic.php?f=36&t=75
Assuming it is SATA then you will need an external enclosure to put it in to connect to another system.
"]click here
This is cheap - but it works. I have one.
If you are happy so far - let me know when you have the enclosure.
It will take a few days to arrive.