Gartner today said Windows will recover from its two-year slump, with total device shipments running the operating system climbing by nearly 10 percent in 2014 and almost 18 percent in 2015.For 2013, Windows' share of the operating systems on all "smart devices" -- smartphones, tablets, PCs, ultra-light form factors, and PC-tablet hybrids -- dropped 5.3 percent compared to the year before, an additional percentage point from the 4.3 percent decline the research company predicted in October, and nearly three times the 2 percent pegged in June.