Basically, you will need a full copy of adobe acrobat. However, there are some 3rd party programs that are allowing you to open and edit PDF files.
Mind you, this all depend on the following :-
* Sorce program that the document what created in.
* Sorce document type. If it was a graphic format, you willl not be editing (let alone selecting) the text easily.
* Security permissions in place on the adobe acrobat file. Security permissions can include this things like :-
- Opening the file
- Printing the file
- Editing the file
- Selecting text from the file.
Converting to an adobe acrobat file is easy. SOME word processors are coming with this function. And there is a lot of shareware that allows you do it too. Check out download.com for some of these programs.