Personally, I just use Canon's own DPP (Digital Photo Pro) software for most of my post work. It's easy to learn, always compatible with canon cameras and easily does the minor adjustments I make on most pictures: ie. RAW conversion, resizing,cropping, white balance adjustment, exposure adjustment, etc.


For more complex or detailed work I use Photoshop CS3. If you're just starting, photoshop is likely "too much" software: there is a steep learning curve. The advantage is that there isn't much that can't be done in photoshop if you know what you're doing.


I'm not familiar with Lightroom, but I've heard good things, particularly with respect to simplifying the digital workflow. I may consider switching to Lightroom myself if the opportunity/need ever arises.


Basically it comes down to how much post work you intend to do and how comfortable you are in working with different software. I suggest just using Canon's DDP for starters and then progressing from there if you need something more powerful.


Stephen