It seems as if the vast majority of the suits of armor and sword hilts and such that we see in most places is just too well preserved or too ornate to ever have been used in an actual fight. Is that observation valid or were these things simply made ornate on a regular basis? Are there any well-preserved suits of armor, for example, that are well-documented to have served in battle?
You're right to be suspicious. Almost all of the armor, and the great majority of the weapons, preserved in museums are very late medieval or early Renaissance, and much of it is ceremonial or parade armor/weapons. Very little survives from the High Middle Ages, and next to nothing from the Early Middle Ages. What there is, tends to be in very poor condition, some of it having been recovered from tombs, others from bogs and excavations, and almost all showing the effects of 600-1000 years of neglected iron. What is on prominent display in these museums tends to skew the unwary visitor's perceptions, especially the children's plate and reduced-scale display armor, which leads to more of the old rot about medieval warriors being five feet tall (archaeology tells us medieval aristocrats were scarcely smaller on average than modern Americans and Britons).
What is a medievalist to do? Well, for one, examine the remaining items, however few of them there are. But, luckily, the people of the Middle Ages left us numerous visual aids. Illustrated manuscripts, such as the Winchester Bible and the Maciejowski Bible, display biblical characters using the armor and weapons of the authors' time. Funerary effigies are very useful as well, these being basically carved relief statues of the deceased, usually in full armor, placed upon his tomb.
To give you some idea of these three sources, I've included links to examples.
http://upload.wikimedia.org/wikipedia/commons/2/2d/St_Wenceslas_chainmail.jpg
http://www.myarmoury.com/view.html?features/pic_spotxi05.jpg
http://www.myarmoury.com/view.html?features/pic_spotxi06.jpg
http://www.myarmoury.com/view.html?features/pic_spotxi04.jpg
http://www.myarmoury.com/view.html?features/pic_spotxii04.jpg
http://upload.wikimedia.org/wikipedia/commons/8/8d/Temple_church_905.jpg
http://www.basedinlondon.com/wp-content/uploads/2010/09/DSCN1168.jpg
http://www.themorgan.org/collections/swf/pageEnlarge.asp?id=267
http://www.medievaltymes.com/courtyard/images/maciejowski/leaf29/otm29vc&d.gif
