Vista - Where, Oh, Where did my Adobe go?

Tried to open a pdf file and I get a box asking me to 'browse' to open with
or 'save to disk'. Adobe is nowhere to be found (except in add/remove in
control panel). It says Adobe Flash Player 9 Active X and another file (that
looks like it just downloaded on 7/21). I don't ever remember upgrading to 9.

Can someone tell me how to get the program to work? I'm sure it's a simple
click here and click there....I'm just not sure where to click.

Thanks.

Annie

P.S. I'm using Vista Home.