Yes
No, you cannot trade between the two different versions because the Pokemon are different or the Pokemon know different moves that are not in red version. When they re-make gold and silver for DS there may be some way to trade between Pokemon fire red and leafgreen to the new gold and silver but I doubt it.
Yes it can. Using the Time Capsule in Gold and Silver it's possible to trade between Red, Blue, and Yellow.
Unfortunately, it is impossible to...
in silver/gold after you get to the seand city but to trade between gold/silver and red blu yellow you have to get to goldenrod
Red, Blue, Yellow, Gold, Silver, and Crystal can trade between themselves. Ruby, Sapphire, Emerald, Firered, and Leafgreen can trade between themselves. Games from list 1 cannot connect with list 2.
No it's not possible. No method of trading where designed to trade between these games.
you trade it from Pokemon red/blue or yellow
No, starter Pokemon are exclusives to every game. They can generally not be caught in the wild. You can't trade between Silver and Fire Red because they are not compatible.
Yes, Pokemon Red can trade with Red, Blue, Yellow, Gold, Silver and Crystal.
you have to trade it from Pokemon red to silver (u need the time machine) then trade it from silver to any version and so on :)
you cannot trade them. you can only migrate them
yes, trade from red, blue, of yellow