In the express share you should see a log file for the database install. Its called dbinstaller.log
If you attach it to the post, perhaps we can compare it to our log files and see if anything is amiss. There are always a bundle of errors in here, where there should really be warnings (where it checks for things like legacy tables to migrate), so just posting some of the errors by themselves might not be terrifically useful.
Also, as a standard troubleshooting step,
1) anything suspicious in the windows event log?
2) are you installing from the server console
3) is there plenty of disk space left
Kind Regards,
Ian./