A: A single mommy with toddler twins! You've got your hands full. First of all, I'm hoping that YOU have enough help and support to get through this stage with the kids. Toddlers demand a lot of emotional and physical energy -- and you've got double that -- AND you're handling it alone! Do whatever you can to get a break now and then. Don't feel guilty about that. The babies need you to be at your best, and everyone will do better if you feel rested and happy.
About potty training: Every child is different. All you can do is offer the opportunity, and follow their lead. One child may be on a totally different schedule than the other --- and that's OK. Don't panic if one makes progress and then seems to backtrack. It's all par for the course. And let me say again -- YOUR sanity is key here! Don't let the desire to get them potty trained make this a stressful situation for you. Take your time and enjoy them as much as you can.
The same goes for activities: Do what works best for YOU. The children will enjoy themselves if you're feeling good. You can also feel free to follow your mommy's instincts about keeping them together -- or apart -- for activities. Some twins really do best when they're together for most everything -- other sets of twins need some independent time. Watch how they do and adjust your decisions based on how you see them reacting. Good luck!