Just remember if the PC doesn't care about the social situation being presented, there isn't much of a success or failure involved.
(i.e. he/she didn't want the relationship, then success might be that the PC is able to side-step the situation without causing a scandal)
a minor noble possibly becoming "interested" in a female PC
Success: female PC has a relationship started with the noble? or is able to graceful step out of it without causing a political backfire
Failure: the noble's ego is bruised and the party's reputation is publically sullied (i.e. The noble spreads influence to do less business with them because they aren't as nice as they seem, etc)
Primary Skills: various social skills (diplomacy to talk your way out of it or sing a song to win his affection etc, intimidate to be more than he can/wants to handle, bluff to talk about how you're already taken, etc)
Secondary skills: ...? (acrobatics/eundruance... umm.. never mind, this is a grandma friendly website

) insight to get a +2 to your next primary skill check to know what types of things might be hot button topics for him, etc
while a young girl from town tries to put the moves on one of the more attractive male PCs. However, the young girl also has a protective father, while the noble might not take rejection too well...
My thought was to have them use things like Diplomacy or Bluff to work their way out of their situations (i.e., the dad bursts in on his daughter just as she jumps into said PCs arms...).
Success: male PC wins over the girl with the fathers approval, or PC wins over the girl despite the father's disapproval, or the PC is able to gracefully step out of the situation without upsetting the girl.
Failure: the girl is upset, the father is upset, or both are upset leading to lessened party reputation in the town (and maybe the father is a big man in the merchants circle in town, or is the only blacksmith, etc)
Primary Skills: various social skills (diplomacy to talk your way out of it or talk your way into the father's good graces, intimidate to bully your way until the father cowers into acceptance, bluff to say it is a misunderstanding
Secondary skills: ...? (acrobatics... to just leap backwards and out the window and run, athletics to have some physical competition with the father to prove worth -- only appropriate if the father is some muscle-type ) insight to get a +2 to your next primary skill check to know what types of things might be hot button topics for him, etc
(we have 5 PCs, so I need to figure out three more ideas on this. Maybe a merchant proposes a business deal for one other PC?)
I am not sure a merchant deal would necessarily make a good skill challenge. It might make for a good role-play opportunity, but skill challenge might be hard. Mainly because, if the PC doesn't "win" the challenge, has he really lost anything that he would otherwise have ? Or does he really care that he can't get the merchant deal? Probably not since it's not something he was initially invested in.
However, if it's something like they'll lose reputation, then that might be a penalty if they worked hard to build reputation or if reputation is something with otherwise observable effects on them.
Maybe something like a young adult boy wants to prove he is just as good or better than the heroes, so he approaches a big bulky type and challenges him to some sort of physical race/swords/wrestling/competition. Success is either winning the competition or talking your way out of it without injuring the upstart's ego too badly. failure might be public humiliation
Or if one of the PCs is of a race (or class, or otherwise "appearance") that is normally stereotyped against, maybe there are a couple townsfolk who want that PC gone. They don't care if he's a hero, he doesn't deserve to be here (or maybe the townsfolk mob claims that the person used some strange elven magic to bewitch everyone, etc). Don't make this too over the top though, or else it would turn in to a party-wide thing rather than a solo experience. Success: able to disperse the mob without issue Failure: PC is publicly humiliated or put in jail for a night (or whatever) for being part of a public disturbance
But, I wanted to make it a quick scene for each PC to see if they maintain their reputation as newfound heroes in town, or if they fail the skill challenge and their reputation changes for the worse.
Does that sound reasonable?
Just make sure that (if failure does mean the loss of public reputation) that the reputation is felt to start with. i.e. before all this starts, be sure to emphasize how easy things seem to be around town for them since they are public heroes. And then as people start failing, describe how it's that much more difficult... prices might be higher in stores, or they have to actually -wait- for tables to open up at taverns, etc.
(just my rambles, take it for what it's worth)...