The available everywhere just makes this an impossible question for me, there just isn't a lager that I like that's available everywhere....
If you allow found in a pub here and there, then Bitburger, it's delicious, and I've found it in at least one UK pub, and in easy kegs in various super markets.
If you allow "good luck finding it", then Dos Equis Special. The stuff is delicious. It is THE best Mexican lager, and probably the nicest lager I have ever tasted, bar none. Luckily shows up periodically in our local Sainsburys now, and is brewed in Mexico, NOT under license. Given Heineken own them now, it still counts as a macro though. :p
Oh and I have to agree, in the 90s Stella and Kronenburg were actually quite nice. These days they're nasty, like every other nasty lager... My first pint of Stella was in the bar on a Sally Lines ferry, and was really nice. Tasted nothing like the stuff sold as Stella now. Back then it was a premium lager, now it's Chav juice...