stay with 7. By the time it expires something new will be out again. Next time consider something like the pro ver. Does have more features to play with.
windows 7 all the way,unless you have a touch screen monitor i think 8 metro just gets in the way.
i got windows 8 standard, cost me 75 quid and i got to say its good so far, really like it, also dont mind the strat bar with the live tiles
If you can get it cheap/free, go for it. If it costs you a bit of money, not worth it.