View Full Path of Current Document in Apps Like Preview & TextEdit

Auto-opening a downloaded file from a browser is done on pretty much a browser-to-browser basis. Since you asked about Chrome, here's the relevant blurb from Google's Docs:

Automatically open certain types of files

If you want certain types of files to always open after they're done downloading, click the arrow next to the file button in the downloads bar and select Always open files of this type. To prevent potentially malicious files from automatically downloading to your computer, this option isn't available for executable filetypes, such as those with .exe, .dll, or .bat extensions (for Windows), and .dmg extensions (for Mac).

Personally, these features weren't visible when I tried it, but then I hardly use Chrome other than for the odd web site test.

Two things you can try :

If you don't need the preview feature in column mode (or for a short term fix), you can disable the preview column by going to View Options cmd-J in Finder and unchecking the "Show preview column" checkbox.

Alternatively, you can disable Quartz 2D Extreme (which should be disabled by default, but may be active and been known to cause Finder and preview slowdown). You can run the following command to disable it regardless.

sudo defaults write /Library/Preferences/com.apple.windowserver Quartz2DExtremeEnabled -boolean NO

Run this command in Terminal (found in the Utility folder in Applications). You will then need to reboot your Mac.