My range is pretty big; I usually sing Soprano 2 in the UW Women's Choir because that's my sweet spot, but I fill in for Soprano 1s or Alto 1s when there's a need for it. I can also comfortably hit the top 3/4 or so of the Alto 2 range but the lower ones cause epiglottal scrape, heh.
The crowd I'm singing for is full of gamers, so I'm thinking Jonathan Coulton's Still Alive (Portal) should go over well, but I want to do some non-video game related stuff, too. Something maybe a little more alto-y for volume.
Mad props to ya (I love the UW Choirs!)
I'm going to approach this differently.
How long are you going to be playing? This is pretty important since the more time you have, the more songs you might want to play. I tend to stick with 1 song = 5 minute rule like I do with open mics or when I'm playing a show, so if I have 45 minutes to play, I do about 7-9 songs. The more time I have, the more songs I do, but I also take 10-15 minute breaks about every hour.
Are you just music for the background or are you going to be playing on a stage or designated location?
Is your uke going to be plugged in to a PA or will it be mic'ed?
As for song selection, there are a significant number of current pop & rock songs that can easily played on the uke that stick to the same repeated chord pattern as John mentioned earlier. I would recommend thinking of your favorite songs and actually print up the chords with lyrics and use a sheet music stand when you play. You can try to cram in the next two months and do it all by memory, but it definitely doesn't hurt to have your lyrics/sheet music in-front of you as well if you need it.
At my last gig a few weeks ago, I had a 30 minute set and did the following songs. I usually sing second tenor and baritone:
- I Want You Back by The Jackson 5 (Key of G)
- MmmBop by Hanson (Key of E)
- Take On Me by A-HA (Aldrine's version in Bm, but I stuck to the actual bridge chords of C#m & G)
- Twist & Shout by The Beatles (Key of D)
- Footloose by Kenny Loggins (Key of A)
I had about two months before the gig and although I did all of mine by memory, I fumbled a bit on two of the songs lyrically and I would have killed for a lyric cheat sheet.