nfs share with wireless laptop

[Martin Ericsson]

Hi!
My home network consists of a laptop, a linksys router and a desktop
computer. I want to share a folder on my desktop with my laptop. I've
done it manually, with "mount -t nfs.." but where should I place this
command to make it mount automatically as soon as my computer connects
to my home wireless network? Can I make it work with networkmanager?

And do I need portmap? 

I've also read that NFS is unstable if you don't unmount your shares
properly, so what happens if the network goes down? Should I choose
samba instead?

Regards,
Martin Ericsson