By default, Ruckus's wlan's should be 802.11 b/g backwards compatible, unless you used the CLI to specify the "ofdm-only" configuration on the wlan (which is often recommended for higher capacity, but restricts the network to G or newer).
You might have to be cautious about using WPA2 (e.g. without TKIP), or enabling 802.11 r or k in the wlan settings. Other than that, they should support 802.11b/g devices just fine.
I've got an R700 and R600 and a thermostat and fitness scale that only support 802.11b, and they can connect to my network just fine, even with WPA2-AES.
Bottom line is, you can expect those tablets to "just work", but be prepared for a possible need to downgrade security settings, or turn off some other advanced networking settings like 802.11r/k fast transition.