The Springfield Loaded Model is a good value for the money. You get a lot of the "upgrades" over a standard Government model or even Springfield's Mil-Spec model at a very reasonable price. Better sights, beavertail grip safety (keeps the hammer from biting your hand), lowered ejection port, etc. Springfield has an excellent reputation for being good, solid guns.
You also asked about the difference in different models like Government and Commander (these are terms Colt first coined). The Government model generally means an all-steel gun with a five inch barrel and full-size grip frame (7 rounds in a standard mag, though 8 round mags are fairly common). This was what the government first commissioned from Colt. A Commander is the same except it has a 4.25 inch barrel. Many consider this barrel to be the shortest possible for optimum reliability in a 1911 style gun.
You will also hear of an Officer size gun. This had a 3.5 inch barrel and a shortened grip frame with one less round -- meaning six rounds in the standard magazines, though mags can be had now with 7 rounds. These guns are also referred to as Compact sized. Now, some manufacturers will shorten the barrel even further to 3 inches.
And just to complicate things further, some manufactures make a gun with the Commander length barrel (4.25 inches) and an Officer size grip frame (one less round) for concealed carry purposes. In addition, you may see references to a "Bobtail" version. This means the end of the backstrap has been bobbled and rounded off to conceal better without sacrificing the additional round.
Finally, some 1911s come with an alloy frame but steel slide. This lighter weight is popular in Commander sized, Officer sized, and the Command-Officer hybrid. You often hear of a "Lightweight Commander." Again, these are Colt terms and other manufacturers often use different terms. However, anyone familiar with 1911s will know what you mean if you use these terms.
From my collection:
Here's a Government-style 1911 (a Colt Combat Elite):
Here's a Commander style pistol with a bobtailed grip frame (Ed Brown Special Forces Bobtail):
A Colt Officer model (Ultimate Officer):
Finally, the Commander-Officer hybrid style with aluminum frame and steel slide (a Sig Revolution C3). It is my daily carry gun in cold weather: