Can one partition be unprotected?

"You need to go to the Dell website & download the Win XP drivers for model.
or you may find them on Dell drivers CD."

In the continuing saga, Gomer finds that Dell insists that it only supports Win7 and Vista for my machine and thus no drivers are listed. However, I went to the Broadcom website and found that the driver was good for both OS. I used Device Manager to copy it, but obviously there are many other things I must be missing.

At this point, I can accept that I can work around the issue of no internet with XP, however, there is the issue of updates. For example, I have SP2 installed, but not SP3. XP tells me I am out of date with my antivirus. Also I have none of the many updates that MS issued over the years. I can go out and get some files with Win7, but often these are just installer programs which need to access the internet to do their job. Catch-22. (If you haven't been in the military or read the book, read it.)

So, my question is: Is it safe to have this unprotected OS on my machine if I do not ever use it on the internet? Everything is up to date on the 7 side. (There is always the option of taking the HD out of the old XP machine and putting it in this machine to transfer those files, BUT there are all the registry entries that don't get dealt with so I'm thinking that would not be a good thing to do.)

Knowledge is a great thing, if you have it. Thanks all