You might get a better response if you include this in a .Net Zone.
I would also split it up. Your questions is big and covers several skill sets which might scare Experts away.
- Reading sub folder names
- Removing Stop Words from strings
- Making web requests and saving the resultant page/file
- Scraping web responses to find the subtitles URI
- Unzipping files
- Downloading trailers - I don't think what you suggest is possible
Several of these would have ready made answers in EE or via Google.