My new isometric RPG/adventure thing...

[Karaman]

You can use DelphiX with JEDI Headers for 2D
It is faster than simple DirectX
I get 100fps always on my 850Mhz AMD no matter how many tiles I use
if they are larger than 30x30

[Alimonster]

I feel for you dude -- I had to get a new hard disc only a few days ago. Still, you'll be surprised at how quickly the code will come back to you. You know all the mistakes you made before and how to solve them now - right?

Anyways, DDraw will always have slowish alpha blending because it's done in software rather than hardware. If you use D3D instead then your blending will be much quicker (older machines won't thank you for it, but new machines will). Perhaps take a look at Project Omega, GameVision, Powerdraw, xcess gdk (does that use d3d?) or one of the other libraries that use d3d (too many these days - I'm losing track of 'em all!).