Grisella's beetle problem is the first side-quest in the prologue of the game.
Quick walkthrough[]
- Talk to Grisella in the tavern in Easthaven. (optional)
- Kill the beetles in the basement of the tavern.
- Report back to Grisella.
Walkthrough[]
When you talk to Grisella, the barkeeper of the Winter's Cradle Tavern (where the game starts), she tells you that she's all out of drinks because bugs have taken over the tavern's cellar where the wine and ale barrels are stored. Agree to take care of this bug problem for her.
Go down the stairs behind her, and kill the beetles there.
This should be very easy if you've already bought weapons and armor for your party at Pomab's Emporium. If you went unequipped, take it as a learning experience about the importance of equipment and heal your wounds by resting in the Snowdrift Inn.
Once you report back to Grisella, you get a reward of 5 
and 1200 xp. She also sells drinks, now.
Trivia[]
- It is a well-worn trope in fantasy role-playing games for the first quest to be "clearing out rats in the basement". The designers of Icewind Dale put a "northern" spin on this, with beetles that are native to the cold climate instead of rats.