"i want to switch my job from windows desktop software engineer to embedded software engineer..."

I recently received the following book details:

-- Embedded C --
by Michael J. Pont
Embedded C is designed for programmers with desktop experience in C, C++ or Java who want to learn the skills required for the unique challenges of embedded systems. The book and CD-ROM include the following key features: The Keil hardware simulator for the popular 8051 microcontroller is on the CD-ROM so that readers can try out examples from the book - and create new ones - without requiring additional hardware. All code is written in C, so no assembly language is required.
http://newsletter.embedded.com/cgi-bin4/flo?y=eHkx0C2HgN0A0BWle0Ah

Note that I'm just passing this on, as the above description seems to fit your situation; I haven't seen the book, so I have no idea if it's any good!
caveat lector