Hi Barry,
It's good to hear you're testing out bicycling as a family activity. It certainly is one that can be very rewarding; It's something the kids (mom and dad,too) can have as a life-long positive addition to weekly routine - or it even may become a passion! We got our daughter out with us in a bike trailer at an early age, bicycled regularly as she grew, and we were lucky enough to go on an overnight 4-day bike tour together during her high school years. I even caught her pridefully telling her friends about it- made for a happy parent.
A couple recommendations (which you may have already tried) on tracking down areas to ride in your region:
Bike Shops- Contact shops in cities and countys in your area. They may be familiar with parks and bike trails in the area that may be suited to novice cyclists - as well as flat and short enough for cruiser bikeing.
Google - try searching "bike trails" and add the specific County, you may find listings for park facility or other trails that would work. As an example, I noticed this link for down in your region
http://haroldoland.com/santa-ana-river-trail. The link includes photos of various sections of the trail. Also, with some extra effort, you can search County websites and look for a County bike Plan - I've tried this when going to new areas and have had luck with finding information on bike trails, streets with bike lanes, or roads they designate as bike routes (no actual painted lane, but a better street for bikes then others).
Google Maps - When you open Google maps, there is a "drop-down" box that can be expanded up in the top right corner of the map. Click on "bicycling" and it loads green lines into the map that are bike trails (it seems these can be dirt mountain bike or paved), streets with bike lanes, or bike friendly roads (my experience so far is the roads shown may or may not may be more suited to more experienced riders). I'm not sure how Google comes up with the info or what standards they have, so i'm not completely sure what to expect from their maps, but it's a good starting point for looking around. Google Maps shows a "trail" around Diamond Valley Lake near you, you may just have to call the park to determine if it is in fact a trail open to bikes, and wether it is paved, dirt, kid friendly, flat enough for cruiser bikes, etc.
When you get out to riding - particularly if your getting out a "long walk away from things", you'll want to be prepared for the occasional flat tire - pretty easy to repair on the road with a little practice, a compact tire pump, a patch kit and tire removal tools. Plenty of water (especially in your area), treats for all, and stops at attractions like playgrounds, ice cream stores, along rivers/lakes go a long way to supplementing the bike experience. Helmets for everyone should be a regular part of any time you hop on a bike, and as you may find as you ride more you may even like to invest in a piece or two of bike specific clothing (bike shorts don't have seams in the wrong places!)
best wishes with the bicycling, Tom
