When you say "into collections", do you mean default? if so, definitely rehab - Sabii lined it out for you.
Bringing this account current, whether by rehab, consolidation or refinancing is the fastest way to move past the penalty, but only rehab can remove the default and will bring your account current, which will yield the best results. The others will just start new accounts, and you will just have to wait for the old account to age off. You have a major derogatory with a 90day late and/or default, and it will significantly suppress your scores for the 7 years it is present.