Noob question re Windows 7
 

I'm aware that as a windows vista business version user, I can install Windows 7 professional using the Windows 7 professional - upgrade pack. Can I still use the same to do a clean install of Windows 7.

I'm assuming the "upgrade" part referes to upgrading the license not so much as merely upgrading the actual software (i.e the "upgrade" media can be used to perform a clean install).

Cheers

Yes. In fact for some upgrades Microsoft requires a clean install of Win7 (but it is still classified as an upgrade). You are able to select clean install for any environment when starting the upgrade process. It may validate that the system has an eligible OS already installed (ie. you may not be able to do the clean install on a new bare drive -- that isn't quite an upgrade). Not sure if this is enforced diligently but I'm sure there are some eligibility checks.

Just choose the "custom" install at the beginning of the process and you'll get a clean install. It is definitely possible and permissible.

Just one note, after you do a 'clean' install of Windows 7 it might leave archival information from your original OS in a folder named 'windows.old'. This can be quite large (freaked me out a bit when after the Win 7 install my laptop SSD only had 10 Gb left with no applications loaded.) Easy to remove using the Windows disk cleanup wizard.

yes, the disk is the same and actually, I believe that the 32 bit and 64 bit installs are resident on the disk as well

I have done clean upgrade installs as follows:

1. Boot from the Windows 7 upgrade DVD with target hard disk containing previous version of Windows.
2. Follow prompts and choose custom install. Setup will inspect your hard disk and when it finds the older version of Windows, it will make a note that you are eligible for the upgrade.
3. Delete all partitions and install to the free space. Installing to the free space allows setup to create a recovery partition and leaves no old files hanging around.
4. Let setup finish install.

I have upgraded a desktop from WinXP MCE to Win7 Home Premium, and a laptop from Vista Home Basic to Win7 Home Premium using this procedure. The upgrades activated without a hitch.

worked fine for me as well