I'm buying a laptop soon and I want to find out what is a better productivity word processor/spreadsheet/presentation program. Most laptops with Windows XP come with both Microsoft Works and Microsoft Office. I want to find out if I work on something on MS Works on a laptop, will the file be compatable later when I open it using MS Office on my desktop PC? Does MS Office come a serial key that is enclosed with the laptop out of its box, or do I need to purchase the software separately? I am more accustomed to using MS Office than MS Works.