Working on two files/folders

I have written many scripts which involve working with two different folders.

For example, “move to”, “copy to”, “remove files with matching names in two folders” etc
So I use Quicksilver to open one of the folders in Finder (It becomes “Finder Selection” which I refer to in my script for the location of one of the folders). I also bring up the other folder in Quicksilver and use a keyboard shortcut which copies its path to the clipboard (This clipboard is used in my script to get the location of the second folder).

I have three questions:

  1. Is there a better way to give my script the location of two folders?
    I prefer to use Quicksilver and then copy the path to the clipboard because Quicksilver makes it easy to find the folder.

  2. Can one refer to the second clipboard item?
    I mean first i copy “xyz” and then I copy “abc”. So “abc” becomes “the clipboard” in applescript. Is there someway, applescript (or shell script) can recognize “xyz”?

  3. How to test the clipboard for determining whether the contents are actually a location?
    Since the location which gets copied to the clipboard begins with " and ends with (e.g. “a:abc:xya:”), it is the only criteria, I have used for testing the contents of the clipboard. But I need something more reliable because some of my scripts will end creating a file in the root folder if the clipboard contents do not refer to a path. If i edit my script which gives me the path to add more characters (e.g. #$*“a:abc:xya:”) aand then make applescript to test for those characters, then i will have to use another script to get path without those characters for my everyday use like: pasting the path in Script Editor or in a document.