First, a disclaimer. I'm not a CS grad nor a math major, so simplicity is important. 
I have a four-character string (e.g. "isoy") that I need to pass as a single 32-bit integer field. Of course at the other end, I need to decode it back to a string. The string will only contain A-Z, and case is not important, if that helps.
The funny part is that I'm starting with PowerShell on the sending end and Linux at the receiving end. I can use Perl or Python there, with a preference for Python. I don't actually need answers in each language, I'm most interested in a PowerShell (C# also good) example for going both ways.
Please take a look at the struct standard library module in Python's Manual. It has two functions for this: struct.pack and struct.unpack. You can use the 'L' (unsigned long) format character for this.
How do I encode a 4-byte string as a single 32-bit integer?