what can I expect to happen at pretrial for first time dui in virginia, with no prior violent or non-violent history (clean record)?

Virginia DUI is a Class 1 misdemeanor.  The maximum punishment for a first offense is a $2,500 fine, one year in jail, and the loss of one's driving privileges for one year.  Additionally, all persons convicted of DUI are, by law, required to lose their driving privileges for one year; the Judge no longer has discretion over this punishment.  However, he may order restricted driving privileges that would allow one to drive to and from work.  All persons convicted of DUI must enter the Virginia Alcohol Safety Action Program (VASAP), a drunk driving program.  This program costs $300.  Of course, since every Judge is different, the punishments can vary dramatically.

There are some sentence enhancements that result in extra, mandatory jail sentences based on high blood alcohol levels - even for first offense cases.  If one's blood alcohol level was between 0.15 and 0.20, there is a mandatory 5-day jail sentence.  If the level was above 0.20, there is a mandatory 10-day jail sentence.  In addition, if one had a blood alcohol level of 0.15 and above, he or she will be required to install an ignition interlock device on their vehicle.

Bottom line, your interests would best be served by getting legal representation.  An attorney who specializes in DUI will be best able to minimize the penalties.  Since this is a very technical area of the law, possibly they can get the charge thrown out or at least reduced.  This is a criminal matter that will leave you with a record, do whatever you can to make sure that you have a lawyer with at the pre-trial.