That looks like a fairly good beginner project. Just look for something with STRAIGHT lines. Believe me, it will make your life easier.
Triangles can come later.
You might want to pick a smaller wallhanging size project to start with so that you will have the experience of completing something from start to finish before starting something bigger. If you are just planning on making the I-spy quilts throw sized, they should be fine as well.
The primary rule of quilting is to use a 1/4 inch seam. Once you have mastered that, and accurate cutting skills, you're good to go. To find a quarter inch on your machine, take a ruler like this and place it under the needle, then use a piece of masking tape to place on the machine all along the side. There you will have a 1/4 sewing line. To practice this, cut out two 2" strips and sew them together, then press the seam flat to one side. They should measure 3.5 inches. Keep trying until you get it right as small mistakes equal big problems in a quilt. It's worth it.
Another important thing to remember is to press the seams where possible in opposite directions so that they will nestle when you go to piece them together. It will make it much less bulky and help you line things up well. Pressing is essential to a well made quilt. Don't iron back and forth as this distorts the fabric.
Here's the tools I would recommend:
a ruler like the one I showed. You'll probably want more sizes later, but this is a good all purpose one.
a rotary cutter
rotary cutting mat (buy large)
seam ripper (probably already have)
batting (I use fusible so that I don't have to baste)
If you decide to handquilt:
A quilting hoop if you are going to hand quilt
Betweens (quilting needles) probably size 10
handquilting thread
I've seen stacks of pre-cut eye spy quilt fabrics on ebay. That might be a way to get more variety for less money.
Sometimes people make a set of laminated cards to go with the quilt as well so that the child can pick a card and look for the corresponding fabric.
Handquilting is simple once you master the rocking motion, but time consuming. I really like doing it, but I have been doing more machine quilting recently so that I can finish up my backlog of projects. I might lean towards machine quilting on this project simply because the fabrics wouldn't really show all of the work you put into handquilting it. Either will work, though.
Binding is tricky the first time you do it, but here's a site with great directions. The only thing that I do differently from her is wait until I have sewn on the binding to trim down the layers. My mom taught me to do it that way in case of error.
http://www.omahamachinequilting.net/
Feel free to post any questions. Have fun!

You might want to pick a smaller wallhanging size project to start with so that you will have the experience of completing something from start to finish before starting something bigger. If you are just planning on making the I-spy quilts throw sized, they should be fine as well.
The primary rule of quilting is to use a 1/4 inch seam. Once you have mastered that, and accurate cutting skills, you're good to go. To find a quarter inch on your machine, take a ruler like this and place it under the needle, then use a piece of masking tape to place on the machine all along the side. There you will have a 1/4 sewing line. To practice this, cut out two 2" strips and sew them together, then press the seam flat to one side. They should measure 3.5 inches. Keep trying until you get it right as small mistakes equal big problems in a quilt. It's worth it.
Another important thing to remember is to press the seams where possible in opposite directions so that they will nestle when you go to piece them together. It will make it much less bulky and help you line things up well. Pressing is essential to a well made quilt. Don't iron back and forth as this distorts the fabric.
Here's the tools I would recommend:
a ruler like the one I showed. You'll probably want more sizes later, but this is a good all purpose one.
a rotary cutter
rotary cutting mat (buy large)
seam ripper (probably already have)
batting (I use fusible so that I don't have to baste)
If you decide to handquilt:
A quilting hoop if you are going to hand quilt
Betweens (quilting needles) probably size 10
handquilting thread
I've seen stacks of pre-cut eye spy quilt fabrics on ebay. That might be a way to get more variety for less money.

Handquilting is simple once you master the rocking motion, but time consuming. I really like doing it, but I have been doing more machine quilting recently so that I can finish up my backlog of projects. I might lean towards machine quilting on this project simply because the fabrics wouldn't really show all of the work you put into handquilting it. Either will work, though.
Binding is tricky the first time you do it, but here's a site with great directions. The only thing that I do differently from her is wait until I have sewn on the binding to trim down the layers. My mom taught me to do it that way in case of error.

Feel free to post any questions. Have fun!