Head over to this topic. This is my Blacklist and firewall rules. I think just the last two rules in the filter will need to be changed for you, my internet interfaces are called “WAN1” and “WAN2”. Yours is “ether1”. if you adjust them for your situation, it will provide you with a pretty secure unit.
http://forum.mikrotik.com/t/blacklist-filter-update-script/89817/1
But also, read up on the Wiki, so you can understand what the script and rules are doing.