Of the two subject cars, Santro is a more preferred car.  However,  WagonR is even better - it will give better mileage than Santro & is more comfortable/spacious(tall car).  Alto (LXi) is another car that is preferred by women.  It gives even better mileage than WagonR & is very comfortable for city drive, especialy for elderly people & women.

If size is not an issue then go for the UVA else go for the Santro

Jiya,

UV-A and Santro cannot be compared head-on since the former is in a segment higher. It also is more comfortable and spacious than Santro. And all the talks surrounding "which car to have if you are a woman" are rubbish. I have seen females driving cars like CR-V and Toyota Prado comfortably while some find it difficult even to drive a humble Maruti 800. Santro's higher set seats will give you a better view of the road all round though. Trust me, women can be good drivers. It's all in the mind!

Blindly go for the WagonR. The tall body and high seating ensures better visibility as well as gives a better feel while driving.  Cost of maintenance is also low and it offers great value for money