I being a noob to the Green Lantern noticed in his movie that he was only able to manifest physical expressions of his power through his ring such as a physical sword or car or track or ray of light etc. Is there any case where he has invoked fear or pestilence or hypnosis or some other non-physical expression through his ring?
No, the green Oan power rings are not limited to generating purely physical manifestations or what are known as light-constructs by the Corps.
However, emotional control (fear) or hypnosis (mind-control) are not necessarily able to be created using the Green Ring. Other color rings may have such emotional control powers (yellow rings can generate fear; violet rings are capable of limited mind control)**
They can generate electromagnetic phenomena such as heat or light, and can create any radiation known to the Book of Oa. They may also project this as energy weapons, beams of force, or radiation streams.
They can manipulate all of the fundamental forces and manipulate the fabric of space time.
They are able to generate space-time disruptions such as worm-holes shortening journey which would otherwise take months even at faster than light speeds.
The rings seen in the Green Lantern movies did not appear as powerful as the ones used in the comics (or perhaps the writers weren't truly aware of how powerful they can be in the right hands).
Capabilities of the Power Ring
Green Lantern rings are very complex devices carved psionically from the material of the prime Power Battery on Oa. They function by creating psychoplasmic constructs comprised of an energy similar to that of the Source. These devices are capable of a number of features little known by non-ring wielders:
The constructs are based in light and do not generate heat nor sound unless unless the wielder wishes it. The emerald energy can be used in a variety of ways, usually it is shaped to form objects of varying degrees of complexity depending on the will power, creativity, and intelligence of the user. The ring is capable of creating any form of radiation and its effects, including such signature and specific signatures such as kryptonite.
There are virtually no limits to the energy constructs the power ring can create, whether giant green boxing gloves or high tech robotic equipment. Some wielders choose a diversity of forms to create while others go for the tried and true.
While there is a psychological advantage of creating an imposing energy construct to unnerve a foe, creativity can only go so far. A strong will is needed to back up that power. Distractions can cause a ring wielder to break concentration and weaken the energy construct. Fear is the greatest enemy of a Green Lantern. Control is needed to wield the power ring effectively. -- Green Lantern Corp
See: > Green Lantern Power Rings https://scifi.stackexchange.com/a/21920/2765