My vote would be Donna/Jason, and Steph/Tim is not open for discussion. :)
Yep! Donna/Jason was cute, tho mostly unreciprocated. Donna seems like she'... idk... I don't want to say out of Jason's league coz he's a good looking guy, but more b/c I just don't see it lasting long. She has certain morals and he's much more willing to break those morals. (Also I don't think she'd idly stand by while he killed people if even they peddled drugs to kids).
Donna/Jason kind of reminds me of the Wade/Siryn "relationship" -- and by that I mean not totally reciprocated b/c one is a "goody-goody" while the other does not so nice things. (Which also makes me think that Jason would totally watch a girl he liked sleep. Just coz then she wouldn't know he has feelings! Oh noes!)