Will this assembler work with Xp and 98? I am a complete newbie to the assembly language, and this assembler. If so is there any special setup or configuration i need to do before i can use this assembler on my systems?

it will run on 9x and NT, and it will generate executables that will run on 9x and NT. Fasm was assembled with fasm

Both dos, win32 console, and win32 gui versions of fasm ought to run on 9x and NT. I personally use the win32 console, I like native code.

there will be some problems in future with longhorn, as it uses only managed C code, compiled at run-time, and running other types is somewhat slower and also before running it pops some message box about app to be possible threat to your computer etc. But anyway, nobody uses longhorn...