N is better. It is faster.
The same as with wireless G card and G router.
Yes, however, your internet speed will only be that of the G router which is comparably slower than that of an N router.
The difference between an N and a G router is all in what the purpose of your router is for. You need to see if you are using it for a personal or business use.
No.
You can't and you don't want to. A "N" router will work with "G" network components and will additionally support "N" hardware at a higher speed. Converting it to "G" would be a step down.
Usually they are, you have configure the router for G wireless networks.
In the wireless properties choose "compatibility mode for G" or something like that. If you do so your router will allow both types of wireless cards G and N.
You can use router of G or N type and the same type wireless adapter. Of course you can use wireless N adapter with G-type router and reverse.
Your wireless adapter probably worked better with the old router. Or the new router is a lower end N router and the old one was a high end G
Yes. B, G, and N work together at the best common speed.
Rather no than yes. It will work if the router is configured to work in the "G" mode.
Yes, you can. You have to configure your router to work in compatibility for G networks.