You will definitely need the MSW for many jobs in this field. That is why I went back to school and earned my MSW this past May.
As we all know, the economy is HORRIBLE now. I live in one of the worst states for unemployment, so I do not want to scare you, but there are NO jobs here, even with the MSW. The few jobs that are available want years of experience, and won't even consider an internship as experience.
Geriatrics is supposed to one of the fields expected to grow, and I have seen ads for nursing homes. Several of my classmates worked in nursing homes in Bachelor's level jobs.
Here is my best advice to you: go straight to grad school. I assume you will have to intern/do a practicum. INSIST that they give you a place that involves the field of geriatrics. That way you will have that experience as a foundation. I could not work during my MSW program, bc it was too intense and the internship and commute took a lot of time. Some of my classmates worked full-time and it was very very hard for them. Maybe you can find a part-time job in a nursing home or similar setting while you go to school (if it is possible with your school obligations). If you cannot work, volunteer as much as you can. You need to get that resume looking good!
My classmates and I are having trouble finding jobs. The ones who were working in the field were able to stay in those jobs, but only a couple got promotions. Several others got hired at the places they interned, but our school had frowned on that because they are afraid of "losing intern sites." The rest of us are not having much luck. I just landed a temp. job for about the next 6 months. It is work I did in my internship, so that helped. I am so lucky I got this, but when it is over, I will be out of work again.
I wish you a lot of luck!