Well I'm back
You can set Windows to save settings which you can then load up on your new PC or harddrive in this case. I don't think it saves the registry so it should be allright, though if it does I'm sorry (it might just save windows settings), i haven't used it:
Programs, Accessories, System Tools, Files and settings transfer wizard. It'd run, searching for settings that can be copied, and then you can write to disc or floppies with the settings
This should save personal settings. (I've never used it though). Instead of clicking 'This is the old PC', you'd select 'This is the new PC' and it'd store files back
As for copying of the programs, its not best to just drag files from the C drive to the cd or something because it won't copy the registry. It would be possible to delete that program manually if you knew what it installed in the first place to the registry.
Anyway, yeah, backup any data files you want. Most programs will just have to be re-installed since you can't do the above (should'nt be that hard though), just save saved files and what else from Documents and Settings like Per says, and from the main program files and you should be okay
System Restore - Useful Tool:
Oh yeah, and when you get the new system set up, start using System Restore much so you can restore settings back if anything goes wrong. You can find this in Programs, Accessories, System Tools, System Restore. You can then either make a restore point, or go back to one if anythings gone wrong. Do this about once a week too.
To check that this is running, go to Control Panel, System, and then to the System Restore tab, and make sure it is set to make some. You can click Settings to select how much space is used. if you can afford it, set this to max as it'll make the most backups auto.
If you ever become choccablock with unneeded ones though, simple delete these by going to the previous menu and selecting to not have system restore using the checkbox, and then after all the files have cleared, click it again.
Good luck with it