How can I find out if I have enough ram to dual boot or boot from a usb? I have a windows xp sp3 laptop with 2gb of total ram and I'm interested in trying out linux (maybe ubuntu or mint), for fun. Windows xp recommends at least 128mb (0.125gb) of memory, and ubuntu's desktop edition requires at least 512mb (0.5gb), although the netbook edition's a little lighter at at only 386mb (about 0.377gb).
I'm not exactly sure how I should calculate how much memory I have available. Should I just add up both operating systems and make sure they're less than 2gb? Or should I consider how much physical memory is available according to my windows task manager? And if that's the case, my available memory varies depending on how many programs I'm running, how should I decide if I have enough space for linux?
Also, a friend of mine told me that if one os is booted, the inactive one won't use up memory. If that's the case, I won't have to add both operating systems to find out total memory consumption. However, my parents said that the inactive one will still use some memory, just not as much, and then they mentioned something about memory being allocated to paging or something. Who's right?
I'm finding this all a little confusing, so as I research how it all works, I'd love it if I could get some help. Linux would be fun to have, but if it adding it might cause a loss in performance it's not worth it and I'd rather just get a job and buy another laptop for it. But that would take time....