I opened my door last night and put the kids inside and then when i went to shut it, it wouldnt latch or stay shut, what can i do to fix it? please help asap

sometimes when it is this cold after car heats up and gets cold again the door mechanism ie latch can refreeze

Door pins are a common failure on that series of Blazer/S10's. Also, another point of contention that the door faces is a sticky latch. Basically, the door latch re-latches itself and when you shut the door into the catch, it slams into it and bounces off. An easy fix is a 3 part cocktail of brake parts cleaner. Open and shut the latch with a screw driver acting as the catch and your interior door handle a few times. P'Blaster, open and shut the door a few times with the screwdriver acting as the catch. Finally, a good shot of white lithium grease. Open and shut the door with a screwdriver as the catch several times. Once you feel it is un-stuck, actually close and open the door several times. If you notice the door rising every time it catches, you MUST replace the door pins (cheap fix). If the door still has issues, replace the door latch (and since you're in there, do some PM and replace the actuator as well).

Here's something that might help you. Look at the door theres a little hook that grabs the striker on car, hold the door handle "open" and move the hook to the open position try to close the door. That should solve your problem. Hope that helps you.

If the latch is in the closed position, simply use a screwdriver to pry as if the door was being opened at the same time as you pull on the handle to open it. This will return the latching part to its proper position and you can then close the door. If the latch is already open and won't close when you shut the door, the quickest way to get it closed is to heat the latch with a blowtorch. Don't get close enough to the door that you scorch and burn the paint but heat the area arond the latch for about 30 seconds or so and the door should latch. You could also do this with a hair dryer or heat gun but it will take longer. Open and close it a few times quickly and it should work properly for a while. To keep it from happening again, once you have it working freely then spray into the latch with some WD-40 or RustCheck. Don't be shy with the spray and get it right into the latch through the door. If it keeps being a problem then before you spray it with a lubricant use a small can of lock de-icer once you have the door working. After that put the lubricant in. Hope this helps.

I think what has happened is that the door latch (the one in the door) has somehow closed and won't let the door shut normally.
Here's how it works. The door latch consists of two major parts. One is the short, round metal tube thing that is attached to the car body about halfway up where the door shuts. Inside the door there is a latch in a slot that lines up with round metal tube thing when you shut the door. I think what has happened is the latch has closed, not allowing the door latch to slide over the metal tube thing and close completely. If you look at the latch in the door slot you'll (hopefully) see what I mean. Now how to fix it.
You'll need a medium to large screwdriver and maybe some help from a friend. First, lift the outside door handle like you are going to open the door. Hold it up. Then, with the screwdriver, push the latch in the door slot UPWARD until it clicks and latches.
It is difficult to put this in words but it usually is an easy fix. No damage done to your car (unless you REALLY slammed the door hard numerous times..).
Please re-post with any questions.

try spraying with wd40 and hold the inside handle and use a screwdriver or your finger to move the latch catches,im assuming that the latches are in a closed position.You may have to unlock the latch with a key first

check to see if your latch is open unlock door put a screwdriver in the latch and open door with out side handel latsh will release

Ok, if you have not slammed the door too hard and you are having a latch problem you need to gather a few things. This works better with two people if you have help. Take a screwdriver and place it in the middle of the latch on the door (where you would expect the bar the latch attaches to on the car would be if the door was shut). Have you other person pull the door handle as if they were opening the door, this will release the door latch itself. As they are pulling the handle, pull the screwdriver towards the inside of the door releasing the latch. I know I have a hard time explaining this method without being able to show you, but this is what you need to do.

very inexpensive. dont replace anything. just get WD40 and spray the latch on the inside very well. then lift the door handle up and get a screw driver and push the latch up. then press it down and repeat. keep working the latch for a whiile. it will work out