yes it was popular, there was even a model produced here: the Timex Sinclair 2068 (TS2068)
We had a factory that produced them here. The model was also sold in Poland.

Zx spectrum 48k was the most common computer model in the 80s in Portugal. Much more then C64.
The selling of C64 was bigger in UK, in 1985 C64 start to sell much then spectrum, but not here.
Computers were expensive, much more then the rest of europe, so the ZX was the only that had a resonable price, well there were others, but the 48k was much more popular around.

Quite difficult to say the best selling games here, but i can tell you that games that were in the arcades, tend to sell quite well. I remember that outrun was a crazy thing! But there are classics that everyone had like:
jet set willy; jetpack; glu-glu; arkanoid; pacman; enduro racer (boy, this one was popular), formula 1 (another hit), match day, and so one, i think the best selling games here were not much different from Uk.