aam.. Well I'll try to clarify some things. First of all I have not bought it yet and I haven't got any win7 dvd-roms and looks like I never will have because I am planning to buy this update from the microsoft store online and planning to just download the update file .
To answer this question, more than likely you'll be offered to download the DVD ISO image file, then you must burn it to a good quality blank DVD disc. I recommend using ImgBurn as it is accurate and has a burn verify feature too.
www.imgburn.com
To the best of my knowledge, there is not an "update" file I have ever heard of, but then again some here say I'm culturally disadvantaged too!
Although some "student" downloads were offered back in Nov of 2009 which was a different type of install, but NEARLY ALL of those download and/or installs were corrupt and MS finally had to send the people who purchased these the install DVDs.
"You can't do a straight upgrade from XP to Windows 7" - when I read the description and the "before buying " notes which clearly says that you can update windows XP to windows 7 but you need to have a clean install , in other words format my hard drive and then install xp again and then put in the w7 update thingy. And my whole pc is compatible with w7 I checked that out and drivers etcetc.
Yes you can upgrade from Windows XP, but it not as simple as popping in the DVD install disc and going from there. I would highly recommend that you save ALL files, folders, photos, audio files, video files, etc., prior to doing an install of Windows 7. Put them either on another hard drive (external or internal) or burn to CD-RW or DVD-RW rewriteable discs.
You don't even need XP on the hard drive in order to do a full clean or custom install as long as you own the XP discs and product key. You may install to a formatted blank hard drive if you wish.
Be sure you download all the correct, latest drivers for your hardware prior to the Windows 7 install and store them on a thumb flash drive, CD-RW or hard drive.
The plan with the update file is to store it on my second partition of my hard drive , since I only have windows on C: and all other stuff on D: so I'll store the w7 update file on D: and format C: and then re-install win xp and run the update file from D: and that should be it... but if I'm wrong please tell me so.
Here is what I recommend you do with this install, and believe me its the simplest way to do it and one which will give the best results too.
1. Do as I stated above and save all important files, folders, etc.
2. MS will send you a Genuine Product Key, save it in a safe place.
3. Burn the ISO image to a DVD and put in the DVD drive, set the DVD drive as the "First Boot Device" the motherboard's BIOS and save that setting. Also if your HD is a SATA drive then set the hard drive BIOS settings to AHCI also.
4. When you reboot, you may see a prompt stating: "Press Any Key To Boot From CD/DVD" Do that within 4 seconds and the install will begin. When you get to the screen showing the drive and partitions, delete ALL existing partitions and then create new ones to your liking. Then let the install begin.
5. When the install is done and you're finally at the Windows 7 desktop, begin to install the Windows 7 drivers for your hardware. Install the chipset drivers first, the the video card drivers, LAN, etc.
brkkab123 your response made me a bit confused. Are you saying UPDATING xp to w7 isint possible at all since those "before buying"-notes says different? And are you giving me instructions for installing a full w7, sounds silly to install two operating systems into the same partition of the hard drive

.
If you'll follow my instructions you won't have any issues. If you need more guidance let us know and we can steer you in the right direction. You may also send me a PM too if you desire.
Excuse me if I did not understand something the way you intended since I study english only as my third language.
Your English is excellent... better than a lot of folks who I have worked with in the past and they live in the USA.
Let us know how it goes and keep us posted!
~Nibs