Some of the region's top conferences and events are held at Lithuanian Exhibition and Convention Center LITEXPO. Look up its schedule and see if anything interesting is on while you're in town.
You'll need to make your way to Lazdynai to reach this events and conferences venue. If you're in the mood for some sightseeing after you're done, why not drop by Vilnius Town Hall? It's close to Lithuanian Exhibition and Convention Center LITEXPO.