Need Help w/Photoshop cs4 & my new 27" imac

So I am a total Newbie to the mac world with just purchasing my new 27"imac this past Tuesday First, I am in total HEAVEN and can't believe how awesome it is, wohooo.. My problem is this. I just upgraded my photoshop cs3 that I had on my hp laptop & got the cs4 for my imac.

Once I got it installed and opened the program, I can see my whole imac background and all the windows I have open, safari, etc??? Can someone please tell me what I need to change or how I fix this???

Thanks so much!!

here is a screen capture of what I am talking about. I was in PS program and you can see everything in the background??

http://i239.photobucket.com/albums/ff37/cgcdesignz/Screenshot2010-01-29at13153PMcopy.png

Open an image in PS an press the button "f".

THANKS.. Now I did that which ofcourse made it FULL screen, and worked, but do I always have to open file first and work in Full screen mode before the background turns to grey??? as once I closed the file, it went back to where I could see my whole imac background??

you can also enable the application frame by going to Window/Application frame (somewhere towards the bottom) ... and no I don't like this option and do exactly what Antares suggested since switching between different views with the "f" key is so easy

THANKS SO MUCH.. i added the app frame and see the grey background now.. but I totally see your point with just switching between the "f" key views.. I guess it will just take me some time in getting use to how things open, operate etc in my imac vs my hp laptop... BIG BIG DIFFERENCE, but for the better

You know the f key works on Windows too right? but on Windows you get the application frame by default and it is just slightly different with opening windows over that gray background, that's true anyway, have fun with your new Mac!

Yes I knew about the "f" key for Windows, but I guess what threw me for a loop was like you mentioned, in my hp laptop by default my ps opened with the gray background, so seeing how it opened in my imac with NO BACKGROUND, had me going HUH??? lol...

Thanks so much & I am def having FUN with my new imac Just can't wait to become a mac pro like the rest of you

What me annoys me much more with the new complete merge with your Mac Desktop is, that you can't have the control panels on an external second screen. You will always have the control panels on the monitor which contains the dock...I hope thats being changed with the (hopefully soon) upcoming CS5!

OMG I totally agree with you Antares, that would be nice to have the control panel on an external 2nd screen vs the monitor