I'm with magicalclick. Writing your own game engine will be fun, but it'll be a while before you see any pay-off from it. Learning a game engine will take time also, but once you know it, you'll be instantly employable!!!
Sounds like you want to go the write your own route
Gamasutra programming section is good:
Here's a good beginner's resource for DirectX:
This book is a very good resource for doing 2D w/ Direct3D (a bit dated, though):
And just remember Gamasutra for anything gaming related, including design