In most cases, resisting arrest is never a good idea. Aside from incurring another charge for misdemeanor or felony, you'll also be sending a message of guilt to the judge or jury. And that is not always good for the chances of winning your case.
In general terms, resisting arrest is the situation wherein you impede the police from performing their duties. In most cases, this involves physically fleeing from the arresting officer. Also counted as a case of resisting arrest is the withholding of information or giving false information to the police. Another instance is the use or the threat of using force against police officers.
There are cases when resisting arrest is justified, but those would be rare. Currently, the extenuating circumstance would be when excessive force and violence are exerted toward you by the arresting officer. The idea here is that even when you're being arrested, you should not be submitted to excessive force, and if you were, you are entitled to defend yourself.
In DUI cases, the best you can do is to ask for the grounds of arrest. You can either question these grounds or give a proper explanation for your behavior. For example, if your car was swerving, you can try to explain it as a problem with your steering mechanism. Just be sure that your car is indeed having a steering problem. If not, you'll be just inviting more trouble if you tell a lie. Telling a lie would not do well with your case once found out by the police. The idea is, if you can explain that you are not intoxicated and prove it sufficiently, then it might not lead to an arrest.
One thing to remember is that once the officer does proceed with the arrest, be sure to go quietly. Aside from that, also be sure to contact a good DUI lawyer or a friend or relative that can find one for you. It is also for your best interest to keep quiet and to refuse to answer further questioning until the arrival of your lawyer.

"You have the right to remain silent. Anything you say can and will be used against you in a court of law."These are very popular lines during a crime scene, particularly in an attempt to make an arre...