For learning, either type is good. The DSLR option gives you high quality images and better low-light performance from the start but it is not essential. Given a tight budget you will find yourself limited in terms of lens options.

For learning, you only need something with full manual controls and a premium compact like the Canon Powershot S110 is a great choice, as any of its rivals: Olympus XZ-2, Nikon P7700, Fuji XF1, etc. Not sure what the conversion rate is but those are under $450 USD. I would recommend one of those over an ultra-zoom like the P510 because they have much better controls, better optics and can produce more shallow depth-of-field due to their bright aperture.

Personally I started with a bridge camera a decade ago and do not regret it at all. It was an advanced model with plenty of external controls (like those premium compacts I mentioned but much larger) and it made beautiful images which have sold just as well as mine from a DSLR, until I stopped using it.

That being said, you can get a used Konica-Minolta 5D and 50mm F/1.8 lens - or something like it - for very little money. It will make your transition to a DSLR easier but the most important for learning is that you start shooting and controlling your camera.