Arduino Project powered by Solar or Battery
I have used the Seeeduino Stalker with Waterproof Solar Kit successfully. I think this kit is a great place to start as it will work out of the box. It consists of an Arduino compatible board with LiPo charger, solar panel input, SD card, real time clock, and water resistant case.

The wireless sensor node kit you suggest is a standalone board for XBees, it would not go with the UNO.

The solar panel and charger should work with the UNO. The battery is the same one as in the Stalker kit.

By the way, the Arduino UNO has an inefficient regulator with about 10mA quiescent current so it consumes a fair bit of power just sitting idle. This can be an issue with solar powered devices. The Stalker has a more efficient regulator. You may also want to have a look at sleeping the Arduino to save more power.