I’m getting a head start on my holiday shopping! My sister and I looooove watching the Office together… it’s one of the few moments of television time we have together where we don’t squabble about the remote control. I can’t make up my mind on whether to get her the season 3 or season 4 DVD though. As far as I can remember, both seasons were absolutely hilarious. Which one do you think has more funny episodes? And don’t tell me to get both… I have a limited budget this year… 
A thousand times season 3. Season 3 is either the series’ best or second-best season depending on how you feel about season 2. Almost every single episode is fantastic, and there are definitely no outright clunkers in the bunch. Season 3 is the show at its best.
Season four kind of muddles along for a while before getting flat-out horrible toward the end.
I’d say season 3. Season 4 just didn’t get the chance to live up to its potential because of the writers’ strike.
Assuming she already has Season 2, I’d go with 3 - it’s a longer season (lots of 1 hour episodes) and it had better content. If she DOESN’T have season 2, that’s the one to go with. My two favorite moments in the history of that show are from season 2 (NO COOKIE and “are you mother goose”?)
Season 3, it is then! I forgot about the interruption of season 4 due to the writer’s strike. I just checked the prices online and it seems like it’s $5 cheaper than season 4. Booya!
She doesn’t have season 2, but I do. 
It looks like you already made your decision, but I still wanted to say that season 3 was about 1,286 times better than season 4.
But the season finale is among the best episodes of all the seasons.
I actually like Season 4 a lot, mostly on account of the PB&J cuteness, but can’t really argue with the people saying you should get S3 first. 
That is all.