UGH! Speaking as someone who can program in 680x0, Z80, Z180/HD64180, 8088/x86, 6502, 6809, 65816, Signetics 2650, PIC, ARM, and PowerPC assembler, I can safely say that 8088 is not a good choice simply because it is so utterly horrible.
68000 really is one of the nicest form of Assembler there is. Admittedly, my main computer is 68060 based (an Amiga), but there are plenty of 68000 development environments, including emulators with step-over etc. available for windows.
There are also many tutorials on the internet.
Yeah I agree too... I hate when people make this statement that you should "start on ___________ (<- insert random 8-bit CPU here)". If that was the true case, then start with a 6502 or 6809, not 8088 (laughs in head)! Assembly language with the 680x0 family is very well balanced and easy to learn with, even absolute beginners should have no problem.