Raising credit score quickly

[ViolentGandhi]

I checked my credit score recently and it's an abysmal 350. I have a couple of collections out and since I just got a job, I'm looking to settle as quickly as possible. I think I owe around $8000 total and I make around $4000 a month. If I call these collection agencies and settle in 2 months, how much would that bump my credit score? How long would it take me to get to a 700 if I paid everything on time from now on?

How hard will it be for me to get car insurance?
I was just wanting some tips for people that have turned their score from close to bankruptcy to a decent level.