See the attached script. It allows for backup of up to 10 SQL express databases, and emails the result via BLAT. Be sure to run BLAT.exe -InstallSMTP to setup your SMTP server and sender address.
Change the variables to match your environment, as follows.
rem --Set Databases to Backup
rem --Set Paths
rem Path to backup to
rem Path to this script and BLAT
rem Backup email recipient