I can see several problems here.. I'll try to go through them all.
First in the validateForm function...
[COLOR=#000000][FONT=monospace]if (validate.checkBlank = "true")[/FONT][/COLOR]
[FONT=monospace]
[/FONT]should be
[COLOR=#000000][FONT=monospace]if (validate.checkBlank() == true)[/FONT][/COLOR]
First, validate.checkBlank is a function/method that checks if any field is blank, right? Then you have to call it (using the parenthesis) to get any value back from it. Second, a single equal sign is used for assigning values to variables and object members, and two equal signs is for testing equality (and here you want to see if checkBlank returns true). Third, remember that the string "true" is not the same as the boolean value true.
What actually happens right now on that line is that you assign the string "true" to validate.checkBlank (so validate.checkBlank is now a string instead of a function).
The same problem occurs on the row with [FONT=monospace]if (validate.checkEmail = "true")[/FONT].
The next problem is in the [FONT=monospace]hwkObj[/FONT] constructor function:
[COLOR=#000000][FONT=monospace]var formIsBlank = true;[/FONT][/COLOR]
should probably be
[COLOR=#000000][FONT=monospace]return true;[/FONT][/COLOR]
since you at one point in [FONT=monospace]validateForm[/FONT] calls [FONT=monospace]checkBlank[/FONT] to check if any field is blank, and then use the returned value to decide what to do (with an if statement).
The next problem is this line:
[COLOR=#000000][FONT=monospace]if (isNaN(id.value) = true)[/FONT][/COLOR]
which should be
[COLOR=#000000][FONT=monospace]if (isNaN(id) == true)[/FONT][/COLOR]
Remember that you put the value of [FONT=monospace]document.form1.fieldId.value[/FONT] in id before, so id now contains a string. Also, we should be using the == here since we're comparing the returned value from [FONT=monospace]isNaN(id)[/FONT] and true, not assigning anything.
The last problem I can see at the moment is the way you use the regular expression to check the e-mail address. I suggest you check out http://www.w3schools.com/jsref/jsref_regexp_test.asp to see how to use regexp. And also from this function you should be returning a value instead of setting the local variable [FONT=monospace]formBadEmail[/FONT] to true.
I hope any of this makes any sense and that it helps you.
Edit:
Just as an additional note... you usually don't have to compare a value with true in an if statement. E.g. these two if statements both works the same way:
[COLOR=#000000][FONT=monospace]if (isNaN(id) == true)
[/FONT][/COLOR][COLOR=#000000][FONT=monospace]if (isNaN(id))[/FONT][/COLOR]