likely is it i they will put me in custody when i report to court?
Criminal Defense Attorney
Since both of your prior DUIs are over 10 years old, the new DUI will be treated as a 1st DUI. Assuming that these 2 prior convictions are your only prior convictions, you should not be very concerned about being placed into custody. However, it would be most safe to hire an experienced DUI lawyer in your area to represent you.
Violent Crime Lawyer
Although your two prior felony DUIs cannot be used to legally enhance your current case, it would be a mistake to think that you will not face any custody time. I am curious: How were your prior cases determined to be felonies? EIther you had several priors at that time, or you were involved in accidents in which someone was injured. Now comes another DUI. The court may well view you as a "menace to society" and exercise discretion to hold you in custody within the limits of the law - now, or at the time of sentencing. There are also DMV and license issues to consider.
I agree that you need the assistance of a qualified criminal defense attorney. Do not delay. And while you are at it, with a record like that you should question whether or not you should be drinking at all. Certainly you should not be driving with any measurable amount of alcohol or drugs in your system. Attending AA from now until you go to court won't hurt your court case; in fact, it may help you in many ways in addition to making a favorable impression on the judge....
DUI / DWI Attorney
The two prior DUIs will not be charged as prior DUI's for this case. However, they may be considered in arguments for bail and sentencing.
As for custody there are too many variables to answer that here. It depends on the Judge, your record, if you have already posted bail, ect. Speak to an attorney who has experience in the courthouse where youtr case will be heard.
DUI / DWI Attorney
Because your priors are more than 10 years old, they wont constitute enhancements in terms of the new charge. However, the Judge & DA will see them and can use them in terms of determining sentencing, so it's better to contact an experienced DUI attorney in your area to discuss possible defenses.