Both are equally good beginner bikes.
The DRZ is cheaper, heavier, has more power. The WR250X is fuel injected.
TBH, you can't go wrong with either choice, and whichever you buy, you might wish you had the other instead for whatever reason. I went through that phase too... I own a DRZ 400S.
Just commit to one and enjoy it, don't worry about which is better. Both can be had for not too much money on the used market.
See my DRZ. It's behind the Gladius.