Desktop app that does some simple image editing

Dear Programming Experts,

thanks for taking the time to read this. I'm trying to develop a very simple desktop application to manipulate images (just rotate, resize, crop and convert to B&W with dithering).

Please take a look at the specifications. I'd like to have a working draft ready as soon as possible. Robustness of code is not fundamental. This application will NOT be installed on the space shuttle or other critical destinations, then a quick and cheap development would be highly appreciated.

The language can be anyone you like (C, C++, VB, etc...). At the moment, I'm only developing a Windows Application (it should work on all versions of Windows from Windows 2000 to Windows 7 without downloading much stuff (e.g., it would be better if the users are not forced to download the .NET framework), but in the future ports to Mac are likely to happen, then your comments about potential portability of the language you're using are highly appreciated.

Thanks a lot! Best

Davide