More secure = less comfortable to use,
Less secure = more comfortable to use
what i don't understind how i'm going to receive or send this coin if i didn't wait for the bitcoin-qt to download all the block, and how he gonna do that if its in a CD.
As far as I know, you can always receive payment as long as you have your bitcoin address, hence no need to wait for the client to download ll the block.
And if downloading all the blockchain sounds annoying for you, how about use some lightweight wallet instead, like Multibit?