About 5 years ago I shared an apartment with my then boyfriend. I was a full time student and he was...?

employed full time and was the responsible party for our bills. On our lease it also stated that I was unemployed and he was the payer of the lease. About 1 year ago when tax refunds were due back I received notice that my state tax return was given to this law office. I called them up and was told that it was for failure to pay last months rent at the apartment 3 years earlier. I never knew anything about it since me and the guy broke up before then and I never got anything in the mail. Long story short, they decided it was my problem and they chose one of us to go after for the money, why they chose the unemployed one I will never know. So Ive been paying the law office $25.00 every two weeks ever since then by check at an 8% interest rate.
What I want to do now, to help with my credit a bit, is to pay them off using a credit card with 0% interest.
Does anyone know if you can use a credit card to pay off collections like this?
I never can seem to get ahold of anyone.

Ask the collections agency if they'll accept your credit card. If you can't reach them (I'm assuming you're trying to telephone them), see if they have a website. If not, write them a letter at the payment address. If needed, register the letter so you know that got it and can't ignore it.
If they won't accept the credit card, see if you can get a cash advance on the card, put the money in the bank and write a check or money order to the collection agency.
Then pay off the credit card ASAP.

Chances are they will accept payment by credit card as all they want is their money...and they would get rid of you as well.
You would now owe the same money to a credit card company instead of them.