noob question about this wireless thingy.. IEEE 802.11n

i know that macbook supports the better 802.11n.. it's supposed to be faster than 'b' and 'g' standard (whatever that is)

but what if my isp only based on 'b' and 'g' standard only? i'm currently using "deconnexion" http://www.danawa.net.my/

so if i buy a macbook, the 'n' standard would become a waste huh? since the isp only supports b and g. so the airport thing is rendered useless.. eh? i dunno about this stuffs.

lag as in spinning beach ball?

is other apps still active when this happens? if yes, maybe you can open up the Activity Monitor from your <system drive> \ applications \ utilities when you run the problematic apps. try to show all processes when you run activity monitor, so when it happens you can see which processor is taking all your processing cycles or you might find that you have abnormal ram usage or disk activity...