As Brian said, you should have trounced those rats. Looking at the stats you've posted for your characters, I see why you had trouble. It looks like you made some less than optimal choices when designing the character, and also left out some bonuses you should have received. I'll just talk about the ranger, and assume you can extrapolate to the Paladin.
From the ability modifiers you posted, I've determined that your Ranger is a human with these ability scores:
Str 13 (+1)
Con 13 (+1)
Dex 17 (+3)
Int 15 (+2)
Wis 11 (+0)
Cha 11 (+0)
Since all your abilities scores are odd, your modifiers are noticeably lower at lvl 1 than they could be. As you level up, you'll add to your ability modifiers, but you only add 2 points at lvl 4 and 8, and then finally +1 to everything at lvl 11. So, if you stick with this ability array, you might have a tougher time at low levels than you need to.
Also, rather than having a balanced array with lots of 13's, you probably want to focus on having a few higher scores and leave the other ones low.
Each of your non-AC defenses is determined by the higher of two scores, so normally only one of those two scores needs to be high. For example, your Will defense is determined by the higher of your Wis and Cha modifers, so you don't need to have both of them at 11. If you moved a point from Cha to Wis (which is what I would do since Wis is much more important for a Ranger than Cha) you could increase your Will defense by one, as well as any powers or skills that use Wis. Similarly, you could move points out of Int to Str and/or Dex without lowering your Reflex or AC.
Your attack modifier is the number you add to your die roll to determine if you hit. In your example, you have +1 for Hit and Run and +3 for Nimble Strike. Right off the bat, it's clear that you're leaving out your Weapon Proficiency. I assume you're using a Longsword for your melee attacks. If you look at the weapons table on page 218 of the player's handbook, you'll see a 'Prof.' column. In that column, for Longsword, you'll find +3. This is your proficiency bonus. Add it to the relevant ability modifier when you attack. So your longsword attack modifier should be
+1 (from Strength) plus +3 (from Weapon Proficiency) equals +4
Similarly, I assume you're using a longbow for your ranged attacks. Looking at the ranged weapons table on the next page, you'll see that the longbow has a +2 modifier. So, your ranged attack modifier should be that plus your Dex modifier, for +5 total, not +3.
You may also have feats or other features that increase this.
Since your ability modifiers are a huge factor in your attack modifier, you should try and maximize the abilities you use to attack. If you plan on continuing to use both Str and Dex attacks, then you should maximize Str and Dex. Your Dex is decently high at 17, but 18 would be that little bit better. Your Str is way low at 13, so I would probably pull points out of the other abilities and move them to Str to increase my melee attacks. Alternatively, you could choose to use only Dex based attacks, as there are a number of Ranger melee powers that use Dex. If you get the book Martial Power 2, you'll see an At-Will called Fading Strike. That can be used with either a Ranged or Melee weapon, but uses Dex for both. It also lets you shift, similar to Nimble Strike. I would point out that if I'm right and your Ranger is a human, you should have three At-Wills, not two.
You should use all your encounter powers most fights. If you're not using them, ask yourself if maybe you should have different encounter powers. In this particular battle, there were only two monsters, so I would've just dumped my encounters on the first one I reached as soon as I could.
If you think you will have an extended rest before your next fight, then there's no reason not to use your dailys. If you think you're going to die, then you should definitely use your dailys, as they're no good if you're dead. Depending on how many encounters you tend to run into per day in your campaign, I would not expect using your daily to be a rare occurrence. I have a campaign where my DM tends to only throw one fight at us per day, so I use all my dailys almost every fight.
Using your 2nd wind is a big judgement call that depends on a lot of factors. I would tend to use it when I'm bloodied and I expect I will be attacked again soon. If I'm far from the fight, like if your Paladin is engaged with both rats and you're off in the corner, then I would just keep shooting until I felt threatened again rather than waste a turn on hit points I don't currently need.