if my blazer sits for more than 2 days w/o driving,it jerks when i step on the gas. (like it is has a clogged up carb) but i have to floor it so it doesn't jerk. then I drive it on the highway for a while and it goes away. would my throttle body need cleaning? or the fuel filter?

 

I would try a fuel filter and a few tanks of high octane gas and some sea foam or fuel cleaner additive. If it still does it then Id clean the carb and maybe check the fuel pressure and stuff like that. Good luck.