in a store
No. Just because they are called shorts doesn't mean they make you shorter.
They are different because shorts are longer and boxer shorts are shorter. Boxer shorts look cooler.
pantalones=pants pantalones cortos=shorts or just say shorts but shorts as in underwear is calzones(same word for mens or womens underwear)
Good mens sexy running shorts are most likely Joe Boxer Short, Shorts. They can an cant be expensive. To find these, look in the mens short section of a clohing store.
They have a lot of pockets for your stuff.
To give the illusion that they are hiding something.
Yes there are mens pants that can be turned into shorts. They are called : Columbia Convertible Zip off Pant Men And you can buy them on www.nextag.com
There are various stores one can buy mens swim shorts both online and offline. Some of those stores are Macys, Amazon, Old Navy, Asos, Nordstrom and John Lewis.