The flights through Nepal and the surrounding countries must be some of the most scenic in the world, weather permitting!
To get the best views you do have to be a little bit cute though!
Generally speaking if you are flying between Nepal, Tibet, India and Bhutan you will find that the Himalayas are best viewed using the following rule:
if you are flying west you need to be on the starboard or right side of the plane, if you are flying east you need to be on the port or left side of the plane.
You may also find that these planes are free sitting, therefore try to get on first and leave that picture of you with the Yeti airplane until you get off!
Enjoy the pics especially the ones of Everest where you can make out all of the features.

Eight out of fourteen of the worlds 8000m+ Peaks are in Nepal.

I think all of them are in the photos here:

Mount Everest (8,848m) known as the highest peak in the world, is located in the Nepal-Tibet border. It is also known by the Tibetan name Chomolangma (Goddess Mother of the Earth), and by the Nepali name Sagarmatha (Mother of the Universe).
On 29th May, 1953, its summit was finally reached by Sir Edmund Hillary and Tenzing Norgay Sherpa.Kangchenjunga (8,586m) means “The Five Treasures of the Snow” referring to its five summits, all over 8,000 meters in height.

Kanchenjunga, located in the Nepal-Sikkim (India) border, was first climbed on May 25th, 1955 by a team from the United Kingdom.Lhotse (8,516m) is located immediately south of Mount Everest, in the Nepal-Tibet border, and the summits of the two mountains are connected by the South Col, a vertical ridge that never falls below 8,000m.

Lhotse was first climbed in 1956 as an alternative route towards the summit of Everest.

Makalu (8,462m) is an isolated peak, also in the Nepal-Tibet border. Its size alone is impressive, but its structure, that of a perfect pyramid with four sharp ridges, makes this mountain all the more spectacular. It has proved to be a challenging climb, as only five of its first sixteen attempts were successful.

Cho Oyu (8,201m) means “The Goddess of Turquoise”. It is located a short distance to the west of Everest. It is one of the towering peaks that stands with Everest well above the surrounding mountains. It was first climbed on October 19th, 1954 by the Austrian team.

Dhaulagiri (8,167m) means “White Mountain”. An enormous Himalayan massif, Dhaulagiri is located in north central Nepal. In 1960, a Swiss/Austrian expedition first reached the summit.

Manaslu (8,163m) is derived from the Sanskrit word “Manasa” means “Mountain of the Spirit”. Its the peak of the Gurkha massif, located about forty miles east of Annapurna, The mountain’s long ridges and valley glaciers offer feasible approaches from all directions, and it culminates in a peak that towers steeply above its surrounding landscape.

Annapurna (8,091m) is a Sanskrit name that means “Goddess of the Harvests” or “The Provider”. Of Annapurna’s many high peaks, five are labeled. Of these, the two highest peaks (Annapurna I and II), stand like bookends at the western and eastern ends of the massif.
The Annapurna range is an enormous Himalayan massif, situated in central Nepal, just North of Pokhara. It has one of the most dominating Himalayan panoramas. In 1950, Annapurna I became the first 8,000 meter mountain to be successfully climbed.