According to your pc specs (here) your mobo has two sata sockets. Before your original hdd dies can you not install your new drive and clone the existing partitions to it so that it becomes bootable as well for backup??? (You should always have backup for your recovery partition)
Good luck
I guess that could be an option -- how do I go about "cloning" a drive/partitions? Do I need separate software to do this?
Not to distract from Dusty's suggestion, but do you think I can just install the new HDD and use the Recovery DVD (or will I indeed face problems)?
Any help is much appreciated!