You cannot disable/remove the LDF file. It has to exist, as it stores database transactions.
What you can do is:
- Set the database recovery model to Simple
This should keep your LDF file from growing. For additional reducing, which I don't think is necessary, you can:
2 Set Auto Shrink to True

3 Turn auto-grow off

Be aware that when a database is in the Simple recovery model, you will not be able to recover to a point in time
Or
- Set the database recovery model to Full (I guess it's already set this way)
- Create a full database backup
- Start creating transaction log backups regularly. It's best to schedule a SQL Server job to do this
The latter scenario provides better disaster recovery as it enables recovery to a point in time
It's up to you to decide how much data you can afford to lose