to preface all this, ive never done any computer building or upgrading of any sort, however it looks like a lot of fun and im curious what all i can do. i have an old windows XP (windows Vista capable) desktop. not really sure how to put this, but i want to upgrade the hardware in it and i dont know where to start... its a Compaq Presario SR1903WM. i know i can get a better hard drive for it but i dont know if it would still work if i got a hard drive and installed windows 10 on it or not. sorry for the confusing mess here but any help is appreciated