It's essential for me that any game runs smoothly. Sadly, SFA 2 for Windows does not. Maybe it's because this game is just a poor port of the PS version.

Basically the game runs skipping frames just to run without slow down. If you change the quality setting to the highest, there's no frame skip and the game runs on 60 FPS, but it became very sluggish, forcing you to use frame skipping anyway.

I hate frame skipping and even a PS2 emulation runs better on my PC than this native Windows game.

For me, SFA 2 is the best Street Fighter ever made, but this port does not keep up with the console quality.

I've tried many compatibility modes on my 64 bit Windows 8 but nothing changes the game speed.

That killed the experience for me too. At first I thought maybe it was my specific setup, but after testing it on several setups I came to the conclusion that it's just a bad quirk of this version of the game. The choppiness is even visible in the promo video to further confirm the issue. I think I've played SFA2 in just about every way it was released and the PC version is the worst for this reason. It's extremely frustrating since there really isn't anything else wrong with it.

If Capcom was only ever going to release one SF game here then I would have preferred the old Dos PC version of SSF2T which seemed to run just fine before I up an lost it. I also would love to see X-Men Children of the Atom again, though I hear it's PC version had a bug that prevented players from using a lot of the combos which is an awful bug for it to have.

Right now the best fix I have for it is to play Guilty Gear instead.

The FPS really did not matter for me. Experiment with different quality modes until you see something smooth. Quality level 2 and 3 do it for me. As far as arcade perfection goes I could care less if the graphics did not match the PS1 or Saturn version of it, as long as the display looked good. If you tried to run the game without the GOG launcher, it would look washed out color wise :(

Yep, feeling like this is just a waste of money when it runs like this... very unfortunate.

Not possible. Those particular ports you mentioned are not owned by Capcom. The DOS port of SSF2T is owned by Gametek and the porting work was sourced out to Eurocom and neither company is around anymore. Likewise, the DOS port of X-Men - Children of the Atom is owned by Acclaim and ported in-house by Probe and neither company exist anymore either. Capcom simply cannot claim their licensees' work and sell them for their own profit. Of course, Capcom could always commission brand new ports and publish themselves, but Capcom is not in a good financial state to make such a bet on these old games just for the PC platform, especially since they just lost the Marvel license.

Rights don't just disappear like you are saying, but someone does have them. It's even possible they may have reverted back to Capcom. Capcom themselves may not even be aware who owns the rights exactly either.

Got it!
I tried some D3D and DDraw fixes and DXWnd with limited success.
Framerate was horribly slow, colors wrong and so on.
I finally got it running well with WineD3D for Windows. :-)
I also had to do a fresh install to get the frame rates smooth and high.

I tried with dgvoodoo and it run fine.

Are you running the game on Windows 8/10 ?

if its your case you can try installing the DirectPlay component. It solves the problem for me . Not only for SFA2 but for all games that use directdraw. These are the steps to do it.

"In the start menu, search as Control Panel and tap it to open the Control Panel.

In the control panel window, select the Programs option.

Now, In the Program’s dialog box click on the Turn Windows features on or off.

In the subsequent window, search for Legacy Components and Click on the Plus Sign.

Then You will find the DirectPlay once you find make enable it and click OK.

Windows will search for the required files.

Ultimately, the windows completed the requested changes and click close.

Now, you can Enable DirectPlay(Legacy Components) in Windows 10."

Credit Jonas24 in this forum.
https://docs.microsoft.com/en-us/answers/questions/108291/enable-windows-10-direct-play.html