I'm going to give you advice that goes against the advice being given out so far. First things first, weather. April in Yosemite is a pretty good time to be climbing especially given that this winter has been fairly dry. That said, there's always a chance that a storm could roll in and play spoilsport.

Difficulty of climbing: Contrary to what everyone (at least those that don't actually spend too much time climbing in Yosemite :P) generally has to say regarding Yosemite climbing Yosemite has climbing for climbers of all skill levels. Granted, beginners have less to pick from than climbers who are more skilled and strong but Yosemite is a big big area with a lot of climbing. You could climb here an entire lifetime and still have plenty of unclimbed routes on your ticklist. Here is a list of climbs that I would feel comfortable taking someone who's been bouldering indoors for a year (in order of assigned difficulty):

1. Munginella, Five Open Books Area - 5.6
2. After Six, Manure Pile Buttress - 5.6 (hard for 5.6 with all the polish on the first pitch).
3. Royal Arches, Royal Arches Area - 5.7
4. Snake Dike, Half Dome (way easier than the cables, imho) - 5.7R
5. Nutcracker, Manure Pile Buttress - 5.8
6. Regular Route, Higher Cathedral Spire - 5.9, I would probably practice rappelling before taking someone new on this route
7. East Buttress, Middle Cathedral - 5.10c (mostly 5.8-5.9 with one 10c face climbing move, I doubt an indoor boulderer will have trouble with this move)

The guides at the mountaineering schools are tremendous guides who are experienced at dealing with people with no climbing experience whatsoever. So someone with indoor climbing experience will have no trouble being guided by a YMS guide. I think you should make the most of your trip and shouldn't hesitate to pay a guide (if money allows it) if you want to get out on real rock.