Problem: Polygonal Lasso Tool Automatically Connects After A Glitch
I've finally found the solutoion, I'm using Adobe Photoshop 7.0 right now, I think this is applicable in later versions too.
You're going to use Pen Tool instead of Polygonal Lasso Tool.
Step 1: Select the pen tool "Default One"
Step 2: Change setting from "Shape Layers" to "Paths" and in "Geometry Options" tick "Rubber Band".
These are the only settings you need to change.
Step 3: Now go on and select the shape you want to remove, if you want to select some inner portion of an image, you can select two paths/layers.
Step 4: Now Press "CTRL + ENTER". Portion to be removed will be selected.
Step 5: Simply hit "Delete Button" and there you go you selection is now gone.
Using Pen Tool is easier than Polygonal Lasso Tool (in my opinion).
This is Salsabeel