What are the most common types of scientists?

Suprisingly, the most common type of scientist is a car mechanic (also known as a mechanical engineering technition) however in terms of what i think you are suggesting, nursing is a really common scientific profession, however if you are looking at science as a career you rock and my advice to you is to play your strengths. Are you good at the biological sciences? if so then i would consider becoming a doctor, Biotechnological engineer, dentist or if you are really keen then you rock even more why not consider a research doctor (i.e. working on stem cell research).
Or if you are a chemist, then why not think of chemical engineering, computational science (not a well known area but i believe one of the easier to degrees to complete), also a pharmsist (this is a really short course, most of the time it takes less than three years full time).
If Physics is your forte, then may i suggest a physisist? they have the best fun (i should know, i am one)! Also mechanical engineering is a highly rewarding area and (my minor subject) Mechatronics engineering. Mecatronics engineering is a pretty new area but is absolutly amazing to say the least. It is robotics engineering (if you have seen iron man that is what i am talking about).
Or if you love each and every area of science, then you will indeed go far in life (check out http://www.brainyquote.com/quotes/quotes/a/alberteins174001.HTML ) some areas i would suggest is perhaps a biological physicist. these are physisists who work specifically with the physics of the body and incorporates Physics, Biology and a little chemistry.
However not to discount the highly popular areas of computer science. This area is challenging but o so rewarding (one of the reasons i took mecatronics as a minor). There are certain machines called quantum computers. These are (basically) computers which will store information on individual atoms. Imagine somthing the size of a remote controll having more memory capabilities than some present day super computers. This highly complex area involves physics, chemistry and obviously computer science.
Now if you don't particularly like the idea of University (or colledge as it is called in some countries) then that dosent mean that you cant have a career in science. A very common, and highly valued, career is a lab technition. This is the kind of job where you can not be over qualified and in Australia it is taught as an apprenticip to students fresh out of year 12.