Why does the initial blockchain download get stuck part way through? I am trying to get Bitcoin up and running on a fairly underpowered laptop and Windows Vista using Bitcoin-Qt 0.5.0.1. After installing and starting the program, I am stuck at at the syncing stage at 92150 blocks and 0%, and have been for several hours. What could I try to get the program working?
Restart OS, restart Bitcoin, try forwarding port 8333 on your router to your machine.  If there is no progress after that, you might consider deleting all the files in your Bitcoin data folder except wallet.dat (if you have made any transactions, deleting wallet.dat will make you lose your Bitcoins). If you just want to use Bitcoins casually, or don't want to wait for the client to sync, you can consider using an eWallet.