Classic. After many hundreds of machines I can write that I've yet to find this works often enough to make it a standard.
But there are many hurdles for you to jump to get to your goal. This biggest one is that you don't have a full Windows 7 DVD. You only have the restore media which in most cases wipes out your carefully crafted partitions.
So that's your first few hundred buck expense.
After that it's a breeze to install 7 with your partitions and install all the drivers and apps. Then and only then are you close to your goal of an OS crash and maybe that partition surviving.
Why not your classic external backup?
And to answer your question, there is no inherent safety in subpartitions. A trojan, virus, fault or user error will not limit itself to one partition.
Bob
I have purchased a notebook -- Compaq with 320 GB hard disk. It came with three partitions: C, 286 GB and loaded with WIN 7, D:11.3 GB loaded with Recovery disk and E: 99.3 MB with HP Tools. I want to further partition C for two reasons: For better organisation of my files and two, if the OS crashes, my other files should not be affected and I must be able to reformat only that partition where the OS resides.
Is this possible and if so how? I wish to particularly know whether we can ensure safety of my files in the other sub-partitions of C in the case of a crash. Shall be grateful for your advice.

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