How to back up a small database in SQL Server 2008 R2 Express Edition
To backup up logins, you'd backup the master database. For any jobs etc, it's be msdb

I assume you want to avoid some complexity by not having 96 log backups per day every 15 minutes. 

Your approach to of hourly full backups will work, but I'd consider doing hourly or 30 minute differentials with a daily full backups. The combination of full/differential:


+consumes less space
+will give quicker backups
+can have more frequent backups (less average data loss)
-slightly increased restore time
-slightly increased complexity