Import gaming is a lot of fun since it opens up a whole new library of games to choose from that were never released in North America.  The only downside is that the Japanese games are usually in...well, Japanese.  There's also that pesky task of figuring out how to get the game to play on your North American System.  Any of the CD/DVD based systems have region code lockouts built into the software/hardware that prevents you from playing them unless you have an adapter, boot disc, or install a chip or switch into the system which involves soldering prowess...something that i can't provide direction on.

What I can provide direction on the Nintendo cart-based systems and a few others.

The following brief guide summarizes some of the differences between the North American and Japanese games and how you can get them to play on your system.  I hope this is of assistance.

North American name:    Nintendo NES

Japanese name:               Famicom

How to play:                  

There are no hardware/software based obstacles here it's simply a physical difference.  The famicom cartridges (carts) were smaller than the NES carts and printed on smaller boards.  In order to play a Famicom game you'll either need a Famicom system or a Famicom to NES adapter.  Some of the first run of the Nintendo first party games released actually contained the adapter within the cart itself.

North American name:    Super Nintendo or SNES

Japanese name:               Super Famicom or SFC

How to play:                  

Like the famicom/nes comparison above, playing a Japanese Super Famicom game on your SNES is solely a physical problem.  The carts are shaped a bit differently but the main obstruction is at the bottom rear of the cart.  The SNES cart has two grooves on the rear bottom for two tabs in the cart port of the SNES to slide into.  The Super Famicom carts to not have these grooves. 

So how do you get them to play?  There's 3 things you can do:

1.  Buy a Super Famicom to SNES adapter

2.  Modify the SNES to play the SFC games.  If you have the original SNES (not the mini version) it's quite easy.  Just open the door to the cartridge port and you'll see two small plastic tabs at the rear of the cart bay.  These can be broken off with a set of needle nose pliers.  Once removed, the Super Famicom game will slide into your SNES and voila! Import gaming has arrived!

3.  Modify the SFC cart by creating "grooves" in the back of the cart.  This is the least recommended method as it can be somewhat messy.  Your cart will be at risk of being damaged if you're not careful.  Just try using a dremmel tool or some other power detailing tool to create the grooves.  Just make sure you don't damage the board inside.

North American name:    Nintendo 64

Japanese name:               um, Nintendo 64

How to play:                  

This is a bit trickier than the SNES but there are 3 methods again to overcome the physical obstructions.  The Japanese N64 carts had grooves in the back like the North American carts, it's just that the grooves are in the wrong place! Here's the 3 methods:

1.  Buy an adapter

2. Buy an N64 tool bit for your screwdriver.  Open up the N64 and remove the plastic plate the sits on top of the cartridge interface.  You will also have to remove the doors from the cart port by doing this which will leave the port exposed to dust, etc unless you keep a game plugged in.  This method is the simplest and cleanest way and doesn't involve any damage or true modification.

3. Modify the cart.  The North American carts have the grooves on the outermost corners on the bottom rear of the cart.  The Japanese cart grooves are inset a bit.  Using the dremmel tool or hacksaw or whatever you used when modifying your SFC carts you can remove the small areas of plastic to the outermost left and right of the bottom rear on the cart so that it fits.