I haven't used XP in years, I am running now win 7, vista was pretty good I thought, did start with win ME that was a mess. Win 8 is not bad once you get use to it, but thats all windows everytime a new one comes out you have to learn how to use kinda like smart phones everytime turn around there is a new one and have to learn how to use it.
You will still be able to run XP but will not get tech support or updates for it, so if there is a security patch that needs fixed you won't get it anymore. Pending on the system your PC has you can step up or upgrade the another windows, I can tell you vista needs about 4gig of memory to run great, can run less but will be sluggish, 7 can run on 2-4 but i have think its 6 or 8 gig of memory and my laptop has never bogged down.