Try CGMiner... https://bitcointalk.org/index.php?topic=28402.0  It automatically restarts dead threads and supports multiple failover mode (switches pools when your main one gets DDoSed).  I'm a big fan.  It has given me better performance and up-time than any other miner I've tried thus far.

And on the issue of letting the cards rest, I'm with MaGNeT on that one.  Run 'em 24/7/365 if you can.  Ideally, you would never have to touch your mining rig once it gets started.