Hi Graeme,
When Titanic hits a berg, she can sustain 100% damage, depending upon speed and how squarely she hits. At 100% she usually settles slowly with the stern going under slightly before the bow, even though she is holed at the bow. She also loses way slowly and has no rudder control.
Different ships go down differently.
If you are using dialup to download large files, you should use a download manager such as GetRight. It can take 30 or more hours to get some updates, with line drops etc.
Regards,
Marty