You should start off by checking out a relevant repair video via a good source for DS Lite repair videos (http://www.nintendorepairshop.com/). Once you figure out how to repair you need a good source for parts, which this website is good for as well.
To repair the microphone on a Nintendo DS Lite you should send the unit to an authorized repair center or technician.
Take it to a DS repair dealer
you can't you need a modded Nintendo ds lite
Send it in to nintendo for repairs
10-20
yes you can
Yes you can. You can also connect DS lite to DS and DS Lite to DSi.
on a ds at the back it does NT ssay ds lite and on a ds lite it says ds lite
You can't download games for DS lite because you need a game cartridge for the console.
It would be pointless to keep the charger unless you have a second DS Lite with which to use it. The DS series have different types of chargers for each individual DS, so a DS Lite charger would not work with a DSi.
you cant because you need to have your recite if you bought it at that store
It is a Nintendo Ds Lite