If you can find the original Windows disk that came with your laptop, then the installation is dead simple as the disk are probably 'recovery' disk and NOT installation disk.
What's the difference?
A recovery disk is built for that laptop. It has all of the necessary drivers and software to bring your laptop operating system to the same condition as when you bought it years ago. You will need to install any updates but that's generally it. As for how you do it, typically, you insert the disk, tell the laptop to boot from the disk, answer a few basic questions (ie are you sure you want to do this? And maybe the Windows key from the sticker on your laptop), and then let it load. Should take less than an hour (probably less than 15 minutes). Once it's done, connect to the internet and start downloading updates.