I need help-fast!!!!. Should I accept a smaller role in my favorite musical or not?

Yes. It's better to get a role of a character with a name instead of getting cast as a n extra. The bottom line is you will get this on your resume`. The leads get to bore the public for hours at a time but your short time might be the most memorable. At the end of the day you can still say you were cast and paid and are familiar with the songs so when it comes along again you will be able to have an advantage. No one starts out on top. Been there, done that and it paid off ;)