During my work, I have been to many temples, and often to the same ones repeatedly; so I tend not to visit them on my own time. I felt I needed to see Angkor Wat, as I was in Cambodia and staying in Siem Reap, which is very close.
The name Angkor Wat refers to a specific temple, the one that I visited, and the most heavily frequented by tourists. However, the name is often used generally to refer to a range of many different temples, some of the same time period, some not, some in restored condition, some not.
If you explore the forest and woodlands in the ground surrounding the complex, you can observe native plants and animals. I was there in the late afternoon, and I can't say I saw a lot. The most common animal around the temples are of course the ubiquitous Long-tailed Macaques. Many are fat from eating handouts.
For me, the highlight is the other common mammal in the area; the Variable Squirrel. As the name suggests, this squirrel comes in an amazing range of colours and patterns.
Access is pretty straightforward. Many companies actually fly direct to Siem Reap from various Asian cities. Once in Siem Reap, it is a half hour and cheap tuk-tuk drive to the temples.