Reset up my laptop

Need help for first time to reset up my laptop

My computer (laptop) is running slow and messed up with many kinds of software and I want to reinstall window xp, reformat it, and other software. I tried HP web siet and failed to find the ones I needed and went to Microsoft web site and failed again. I might not fine right ones? Please help with the steps/instruction or the web sites.

Thank you ahead of time