This is a common problem with digital, which has less dynamic range than film. Most P&S cameras tend to expose for the darkest part of your image (like the tree trunk) such that by the time it gets to the sky there's nothing left and it's all white.
Find the exposure compensation control on your camera and try setting it to -1 or -2 and you'll probably get the sky back properly. At that point the tree trunk (first photo) will be underexposed though. If flash is viable, you can set the flash to the slow sync mode which will help. Otherwise a lot of the software out there will pull up shadow detail for you. The point and shoot cameras that I've owned have all generally needed to be set at -2/3 EV compensation for "normal" looking photos. They all tended to blow skies out, which from reading reviews of other cameras is pretty much the norm. Even both of my Nikon DSLRs do this.
slight underexposure could help...
BUT. The biggest problem, is the direction of the shot. If you shoot towards the sun at all, the sky washes out to a white or light blue. Shooting away from the sun is the best solution (other than sunset and sunrise which barely matters)
A polarizer or ND filter would help here. Your sky is white due to over exposer of the sky. This is why landscape photography can be a difficult area to master