If you had a lot of TITAN transactions/orders, you may want to download and rescan the whole chain (there is a copy of it floating around so you don't have to sync from scratch). Otherwise, you don't need the chain at all.. and also when I perform wallet recovery I set my firewall to deny all incoming/outgoing connections for the BitShares 0.9.3 client, it seems to run way smoother when not trying to talk to the network.