newbiie: Can i make this with adruino ?

Hi, so what board is best:
Arduino Mega Atmega1280

or this one
Arduino Uno

Would this be ok for the relay ? i would prefer a latch relay can i buy one and connected it directly to the adruino ?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150495558944&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

Can y buy this one

http://panasonic-denko.co.jp/ac/e/control/relay/power/specdetail/index.jsp?part_no=ADJ13005

how to connected ?

i can't find the module to measure voltage.
How to connect this to the adruino ?

thanks