I want to SELL my laptop but I've had some documents on there with important information...so I need to somehow wipe it off the laptop before I sell it, as I know that you can recover files if you know how to do it. And if someone got HOLD of my info such as bank details etc. that would be bad. Does anyone know of a way I can wipe this information effectively?
I would really appreciate some advice or suggestions! Many thanks. If there was anything that private on the hard drive, I'd install a different hard drive and then install the OS to it like new for the new owner. You can get hard drives PRETTY cheap these days. I bought for example a 160GB 2.5" SATA HDD for $29.99 online about 3 months ago for a laptop that I rebuilt to sell and the only available HDD I had was a 40GB SATA drive which was really too small of capacity for a somewhat modern laptop. With installing a different hard drive and retaining your original hard drive there is no way for anyone to try to get the data back because it never existed on the hard drive platters to recover.

There are also programs out there that can write a hard drive with 1's and 0's to OVERWRITE where data existed, however these are not as perfect at getting rid of data as completely swapping a hard drive is. Your first step should be to reformat the drive as this will clean out the physically allocated files, then install a fresh version of Windows. Now you should only have virtual traces of your original files and physical copies of Windows files on your drive. Your next step should be to download and run a program such as Eraser  and to delete all virtual copies or file fragments off of the drive.

http://lifehacker.com/5966580/what-should-i-do-to-my-computer-before-i-sell-itPull the drive...i agree.

Out of all the used systems i've sold or donated i kept every HDD...Just to be on the safe side, I would prefer to keep the old drive with me. And put in another drive for the new owner as suggested above.If you laptop has the option to make recovery discs then do that. Test that the recovery discs work by booting from them and starting a restore. Then wipe the drive with dban or Parted magic's wipe disk. Then run the restore from the recovery dvd's. You should make the recovery disks even if you replace the hard drive. It devalues a laptop if it has a generic COPY of windows loaded instead of the manufactures version with all the additional tools and correct drivers.

Another option is to delete the files and then use kill disk   http://killdisk.com/wiping.htm. To erase any traces of the files. This is risky as there may still be traces in windows that would be enough for an expert to piece together a lot about you.Hey! Yeah I think I will pull the hard drive, thanks for the suggestions! It's better to be safe than sorry I guess. I am also paranoid about this sorta stuff cos nowadays you can achieve pretty much anything.