I use Photoshop CS2.
However, my old computer died and I'm now using a computer with only 10GBs of space (total) and, just in general, much less everything than any computer out there. That combined with an extremely slow trickle for an income that I would use to repair my old computer or get a new one has pretty much left me out-of-action for quite some time.
So, yeah, I'd imagine if Paint.NET is giving you a hassle, PSCS2 won't do you any better. Still, it's better than the Gimp.