As far as I'm concerned a jeep has to be a Willys, WWII Ford script or perhaps a Kaiser jeep to be a classic. However, what constitutes a "classic" to the DMV varies by state and availability of classic car insurance for a particular year, make and model varies by insurance company.
It is unlikely that any state DMV or insurance company will consider a 1997-2006 Jeep Wrangler to be a "classic." Also, you should be aware that one of the trade-offs for discounted classic car insurance is a strict limitation on how many miles it can be driven each year and sometimes on how it can be driven (parades, car shows, occasional weekend use, etc).