I got a laptop today, but it came with the hard drive partitioned in two. Is there a way to "de-partition" them without running Setup? I'm using Win XP Pro SP1, by the way.

Why do you want to take that partition out. What size is the drive and what is the break down. The partition is there to access files faster. But if you dont want that partition magic will do what you want.

Any decent partition management program will do the job. Only problem is, any decent partition management program is a commercial one. There's no decent 'freebie' that I've ever heard of!

http://www.ranish.com/part/

A free partitioning tool but you need to know what you are doing to use it because it is all manual entries and no nice graphical interface like the commercial ones.

I don't think that utility handles NTFS partitions, does it? I certainly would not use it on a Windows XP system.

I have a computer I bought for my son and the hard drive is 20G but it is partitioned into 3 drives. It came with the recovery disk, but when I rebooted the operating system I did not know about partitioned hard drives so I did not change the 3 dirves to one drive. The C: drive has only allocated 2.99 G and is full but the other 2 dirves are 100% empty. I want to fix this problem without losing all the upgraded software I put on it since reinstalling the operating system. What should I do?

You cannot do this from within Windows XP itself. Simplest is to get one of these free tools; they will allow you to delete the two partitions and then extend the C: partition so as to occupy fully the available space. All are quite straightforward to use.
GParted, a Linux tool which is a bootable cd package... http://sourceforge.net/projects/gparted/ - you want the LiveCD package; dl and BURN the .ISO. Directly.
Or there is Paragon Partition Manager. http://www.paragon-software.com/home/pm-express/download.html -the free version will suit your needs, make either a bootable cd or flashdrive.
Or EASUS Partition Master. http://www.partition-tool.com/personal.htm - does the lot.
good luck.