I'm not technically knowledgeable enough yet to give you a real "critique" but I think it's always nice to even just hear honest opinions of our work. So keep that in mind when reading my stuff.
I really like the first two. They have a very clear foreground/middleground/background thing going on, and the mountains themselves are spectacular.
The third picture I can't say much for, it seems to be a decent enough picture, but it also just seems kind of boring to me, for lack of a better word. What were you thinking about when taking this picture? What struck you to photograph that specific thing?
I really like the fourth picture as well. The only thing I think detracts from it is the two white buildings in the far middleground area. They make the scene a bit busy, but I still really like the picture. Very nice angle and view of a good scene.
Again, keep in mind that I am very new to all this as well. Don't even have my dSLR yet. (Although I'm getting it Wednesday! FINALLY!)