The trouble with Photoshop...and the ONLY trouble in my opinion, is that it is expensive, like Jinx said above.I recommend, especially for a beginner-ish
to grab Photoshop Elements. It's a slightly toned-down version of PS, but only for $100.
(And if it's anything in the 'toned-down' dept. like Adobe Premiere elements, you're NOT gonna have a watered-down Photo editor, rather, you're going to have a great one as opposed to the original God-editor.
It does take a few days to get into it. But once you do, it's smooth sailing, and a day of goofing around will merit unbelievable rewards in skill. It's kinda like drilling in a screw...once you puncture the surface, it goes right in very quickly.
But to answer your original question, nobody does it like Adobe. and though the 'other' editors can be nice, they simply can't compare to PS (why do you think the best, like Jinx and I, use it?
As for old vs. new...are there really any HUGE differences between CS2 and 3?
Just curious, I haven't been able to grab hold of a CS3, yet.
If you care to spend 2 hours* downloading, go to Adobe's site, and they'll let you download a month's free-trial of CS3, and elements if you care to do so.
*download times based on internet speed. Printed approximation achieved at 100kbps.