No discs or hardrive version only bit more trickier follow this link on wikihow.
http://www.wikihow.com/Reinstall-Windows-XP-Without-the-CDWhat model and make is the laptop and roughly how old?
Make a note of the OS serial number, should be on the bottom of the laptop along with its details. Make sure it is plugged in not running on batterys, reinstallis a energy hog.
As you're virused do not back up aything the virius are live and will move with anything you back up. Soon as you put it back, back they come.
If you have the original rescue disks follow this.If you have. first thing is if you are infected, as you are. NEVER DO A RESTORE FROM A RESTORE POINT. virus's head and infect it.
To to an install, put the orignal disc in, turn off and turn on. Each start up sequence is different. Mines says hit enter to install for CD. Yours will say something similar. Follow it and it will take you through the steps.
I would suggest a fresh install as it will ensure the virius's are removed. I usually wipe (FORMAT the drive and my MBR then I'm a bit more experienced in doing this and like the gungho approach) the lot off some differ and keep the old settings and files but it can keep the virius's in them. Up to you what you go for.
Old setting and files are usually found in the main drive and are marked C: drive windows old.
The resintall sequence is step by step fromt he CD's and you may have to re-add the drivers.I have 2 discs, windows and my drivers and also a recover on my e/drive.
You can add the drivers in the reinstall sequence, it asks you.
It will take time to do it and then when its finished you've got to update it via the windows update, add a firewall and antivirus. I would make the antivirus run itself regular if the lad doesn't do it. It'll save headaches like this.
Does that make sense?
This is and XP set up, might make a bit more sense and lets you know in advance whats coming up. All Wndows are roughly similar in set up terms.
•Files will start to load from the CD to begin the installation. Eventually you’ll be asked if you want to install Windows XP. No need to type an essay here on why you’ve made the decision to do the installation. Just hit Enter.
•Next is the End User License Agreement or EULA which must be accepted to continue installation. Press F8 to accept, F3 to bail out now. You can read the EULA if you want, but it adds two days to the installation time.
•The next screen displays the available partitions where XP can be installed. Select the one you want and tap that Enter key again to move on to the screen where you select a file system.
•It’s time for that important decision. FAT32 versus NTFS. The preferred choice is NTFS. It allows security features and stability that aren’t possible with FAT32. Apply the knowledge you gained during the preparation phase at this point. Make your choice of formatting options and press the F key to start the process. Once the format process completes the installation will continue.
•If you are installing from a full version Windows XP CD the installation continues without intervention. If you’re using an upgrade version CD this is where Microsoft confirms your eligibility by requesting the media that allows you to use the upgrade version. Insert your media in the drive, let the verification complete and reinsert the XP CD when prompted.
•Setup continues and eventually the computer will reboot. Watch the onscreen prompts but do not press a key when the “Press any key to boot CD” message appears.
•Installation will continue, prompting you from time to time to supply some additional setup information. Feed the prompts with appropriate responses and eventually another reboot will occur, this time bringing you back into Windows XP, depositing you at the Windows Activation screen.
•You can either activate your copy of XP now or delay the activation for up to 30 days and suffer the periodic activation reminders. I suggest you activate now and register at the same time. It’s really painless. In any case, activation is required at some point or after 30 days you’ll be denied access to the desktop. Registration is entirely optional.
•The last step is to enter a username and watch the XP desktop appear, ready for use.
Congratulations. You’ve just completed a clean install of Windows XP. Look around, explore, play with the settings and start installing applications and transferring your data backup. You’re not in Kansas anymore. This is Windows XP.