The first thing I do after a new install on a customers machine is go to Microsoft via Control Panel and get all the latest updates Nige.
The UAC is also in Windows 7 but not as much as Vista and I live with it but you never know when something that's nasty may want permissions so it's up to you if you want to turn it off.
You can leave Defender alone if you want, I never found it much use in my Windows 7 machine anyway.
Malwarebytes and Avast are perfect by the way but on the browser I use Firefox as I'd rather stick pins in my eyes than use IE.
Get the updates Nige and then get back to us mate.
EDIT: I just noticed the partition aspect so can you include a screen shot of what it says in Disk Management in your next reply please.
Edited by Wolfeymole, 12 January 2013 - 11:01 AM.