Hi,
You are correct regarding this being an issue with win7 32bit.
32 bit operating systems such as Win7, vista and XP can only access disks up to 2 TB in size as they use MBR (Master Boot Record) type partitions which until recently have been fine for most peeps.
The 64 bit varieties (XP 64 pro can access larger but not use as operatiing system drive) will switch to GPT (GUID Partition table) type partitions upon recognising a drive of larger then 2TB in capacity. This allows 128 partitons per drive (MBR maxes at 4) and will access drives of some stupidly large size
This means that once you have set up the drive (and assuming it doesn't ahve the OS installed on it) you should be able to run it perfectly well docked externally. Obviosuly if you ever need to read data from this, you will need to make sure it is hooked up to a PC running a 64bit OS.
One caveat for booting from a GPT created partition is that the motherboard must support UEFI, which started to be heavily adopted last year, tho it has been around for a few years.
