It will likely come with at least 3 partitions:
System Reserved (very small, about 200 MB)
Recovery (maybe 10 or 15 GB)
C: for Windows
And maybe even a fourth partition, such as for tools of some type.
That's OK, as long as you never have to add another partition. If so, you would have to use an extended partition--which is doable.
There are advantage and disadvantages to single or multiple partitions. It's mostly personal preference. There's nothing necessarily wrong with 1 huge partition, subdivided only by folders. If you chop the drive up into 5 or 6 partitions, you may end up running out of space on a partition sooner than you expected---which is a pain.
You could do this:
Make DVD recovery disks when you get the PC. These discs serve the same purpose as the recovery partition. If you have the DVDs, you could delete the recovery partition and still be able to restore to factory condition.
You can delete any "tools" partition to the extent you don't need the tools. You can likely find equivalent or better tools on your own.
You could even move the stuff on System Reserved to C and then delete System Reserved.
You probably won't get a Windows install disc, but you could download a legal Windows ISO file, burn it to a disc, reinstall Windows from scratch, and set up your partitions any way you choose in the process. The HP will probably have all kinds of crap on it that you won't want and you can avoid all of that with a clean install after burning recovery disks.
I assume you will have only 1 internal hard drive? In that situation, most people here who build a PC from scratch would probably split it into 2 or 3 partitions: C for Windows (maybe 60 to 150 GB), D for data, and System Reserved if you want to use System Reserved. It's a totally optional partition that can be avoided in a clean install.
