Which of these digital cameras are the best buy?

Sony w310
Canon A3100
Canon IXUS 130
Sony w530
Nikon S5100
Sony W350
Sony W360
Casio EX-H15
Sony W390 (but a bit over budget but if superior photo quality and speed and overall then I might buy it)

Canon a3100

Whichever one has the features you need.

You can consider Nikon Coolpix S5100 12 MP Digital Camera with 5x Optical Vibration Reduction (VR) Zoom and 2.7-Inch LCD (Black)

12.2-megapixel CCD sensor; 5x wide-angle optical Zoom-Nikkor glass lens
2.7-inch bright (230, 000-dot) display; 4-way VR Image Stabilization system
HD (720p) Movie with one-touch recording for easy operation
Smart Portrait System; 18 Scene Modes including Scene Auto Selector
Capture images and video to SD/SDHC memory card (not included)