I know this sounds pathetic, but I'm on Slums in Dorter. I win when..

This is one of the difficult stages early in the game. One thing you could do is continue to train your characters until you have access to classes like Lancer and Ninja. Or you could do this: the enemies are three archers (one with longbow, one with crossbow, and one with no weapon), two Wizards (casts fire, ice or bolt), and a Knight that has the charge command. You could train Ramza as a knight and have him learn Weapon Break (400 JP) and then change him to a Archer. This has a large benefit: you can destroy the knight's sword from a distance, making him a weakling. For the Wizards, you should be able to kill them with two or three Fire spells. Archer with longbow: Deltia and Algus will go after him in the begining, but can later face trouble with the other two archers and the Wizards. Just focus on the Wizards first, then the knight, and lastly the archers. It will take a few tries before you are finally victorious. It is EXTREMLY easier if you have a Wizard with spells like Fire 3 or have a Ninja with Double Sword. But take your time and pay attention to who you move and what the computer does. You can usually learn the computer's pattern after a few plays on a stage.

This is acctually really easy you need

1.)ramza kight or squire

2.)a piest with cure and raise and the knights ability equip shield

3.)a kight with move +1

4.)a monk with the ability wave fist

5.)and they all need battle boots

I always do this and I win first try .o and your characters should be about level 6~8

Change Ramza into a Monk. He'll do a lot of damage, but be careful with him because his HP will drop a bit from a squire. Protect your people right at the beginning of the battle. Take your black mage but don't move up too close, just close enough that you can place the magic spell in the panel ahead of the enemy (just make sure they won't move first!). Give all your people battle boots so they can get away if they need to. Have at least 3 people with some form of healing/reviving. Sorry to say that Delita and Algus really aren't much help in this battle. Just make sure they can get to the archer at the top with battle boots and see if that helps you!