thank you black pearl and inkista!! great advice and directions there

delighted to know that i can use all FX lenses (with even greater results). so, as i understand, D5100 doesn't have a focus motor and won't focus without SWM in lenses. i'll be a little specific here..i intend to do a lot of low light indoor shooting so i will be aiming at inexpensive normal lenses(like a 50mm). i see the AF Nikkor 50mm f/1.8D at the nikon site below:
http://www.nikon.co.in/productitem.p...106-387119c054
as i see, it's a AF lense, not AF-S. does this mean it doesn't have SWM n won't autofocus on a D5100??
also, i would appreciate if you can guide me with the significant differences between a 550D(rebel t2i) and a D5100 which will affect my photography in long run as i'm an amateur.
thanks again