I know I had to take a mouse to use when I was working on my aunts laptop the touch pad stuff is uncomfortable for me to use - but she is used to it - she didn't even want to try my optical mouse.
she does have upper back pain so i thought a mouse might be a good change - but she isn't on her pc a lot.

I like my desk top and big chair {a executive style lazyboy desk chair}- it's pretty well set up ergo wise I think. Arms/desk/chair/monitor height, footrest etc.
I can tilt chair back and put legs up on the desk for a change if I'm just surfing around and not typing anything.