-- Priyanka is sexier, but her features aren't that great. Kareena looks more glamorous, but her jaw and face shape makes her look a bit manly. So I'm going with Priyanka here.
Rani vs Vidya - Ahh...the fashion-disastrous aunty vs. the botoxed fuzzball. 😆 In her prime Rani looked pretty good, but her "current" look with the immovable botoxed square face is enough to scare off little kids. Vidya can always change her attires I suppose (not that she's inclined to, but still)...so her. That said, Vidya doesn't have an iota of sex appeal in herself. She's got a good 'classical' face.
Aishwarya vs Preity - Ash, but she looks pretty "meh" now-a-days. Yeah she got pregnant, but as far as my memory serves, she started gaining weight from much earlier. Also, yeah she's aged, but there are many who manages to still retain their beauty even as they age; unfortunately, Ash isn't one of them. Preity was never an earth-shattering beauty, but still very few could touch her cuteness in her prime, and she still looks fresh.
Karishma vs Juhi - Juhi. Sorry but IMO Karishma had a very manly face back in the day.
Kajol vs Madhuri - Madhuri, like no contest. Kajol's eyes are gorgeous, but there's nothing about her facial features that are remotely "beautiful".
Raveena vs Sonali - Sonali.
Deepika vs Sonam -- Umm, both are "pretty", but neither are as exceptional as their magazines and media tell us. I'd say they are pretty even, though I find Deepika far more graceful and possessing of screen presence than Sonam.
Lara vs Bipasha - Lara, but Bipasha's sex appeal is almost unbeatable.
Sonakshi vs Anushka - Anushka ... before the surgery disaster.
Parineeti vs Alia - Eh
Illeana vs Esha Gupta - Eh
Asin vs Amrita Rao - Amrita was a pretty face back in the day (don't see her now). Asin is, well, just sleep-inducing.