Microsoft Surface with Windows RT has an ARM-based processor. Currently, the applications that can run on the platform are somewhat limited because Surface is still relatively new.
1. Is there an app for my Surface that allows me to highlight and put comments PDFs created by others?
Adobe Reader for Windows 8 Tablets (Windows Store app) runs on Surface. But it only offers the basic viewing functionality so far. We will be adding more features (such as viewing and editing of Sticky Notes and Highlight) in the near future.
Adobe Reader XI (desktop app) does not run on Surface.
Microsoft Reader (built-in XPS and PDF viewer) can add Highlight and Notes.
2. Is there an app for my Surface that allows me to generate PDFs from other applications?
Microsoft Word (as part of Microsoft Office that comes free with Surface) can export a Word document to PDF.
3. Is there an app for my Surface that allows me to read Adobe DRM protected books that I bought on the Sony Ebookstore?
You can probably find the answer to your question in the Adobe Digital Editions forum by typing "Surface" in the Ask a Question search box at the top of the page.