Basic Design App

Hi there,

I'm looking for a Mac app to help me design headers for some of my blogs - basically, all I really want is a straightforward way to:

- Open a new image of a set number of pixels (900x200, for example)
- Copy and paste a few photos in and be able to click on them and individually drag to alter their dimensions.

I know I could use something really simple like Paintbrush for this, but I want individual control of each the elements I drop in, after they have been dropped, if that makes sense.

Forgive the noob level of the question but I am a techie, not a graphic designer. The last time I did something like this I used Harvard Graphics under DOS 5!

I have Gimp but I think I really need a vector graphics app. Have downloaded Inkscape but it is way too complex for what I want to do...Can anyone suggest anything?

Many Thanks