Well if I could play Blazblue or Disgaea on my PC I'd never buy a one but unfortunately it does not work that way.
You
can play Disgaea on your PC, though. Some of 'em, anyway. If your PC can handle a DS (likely) or PS2 (less likely, but still possible) emulator. Only legal way (for now, anyway) of doing so involves owning the console in question and then technical shenanigans far beyond my personal capability (mostly relating to bios extraction or whatever), but it's possible.
Not so sure about blazblue, but, well. Matter of time and all that.
And now I'm wondering why the console folks don't just make a PC compatible OS. Have a disc or small hard drive whatever that lets a full blown desktop dual-boot the console OS, provide USB controllers, go the whole nine yards. I can't help but wonder what the profit margin increase of doing that would be, assuming any occurred once you factor out the console itself (and you could counter that partially by selling the OS disc or whatev' for a fair penny, not that I can see the consoles making up much of the profit anyway, given how freakishly expensive console games are... ). And more importantly, which of the big boys are going to realize the (what seems to me, to be) obvious first and do just that.
If any of them do any time soon, anyway. The vaguely neurotic controlling tendencies (to the world view of someone that's been thoroughly inundated by the internet's general ethos, anyway) of those guys might not be willing to let go of their proprietary silliness in a reasonable time frame...
... which then makes you wonder when the outside party's going to come in, because given the situation it seems like things might be (or soon be) ripe for one.