Tabulating

I have a couple of queries regarding tabulating.

1.     Are we able to set tab stops at different intervals besides the default ones already set and if yes, how?

2.     Is there anything that I can do that will speed up the tabbing process?  e.g. the time it takes to go from one field to the next.

3.     Is there anything that I can do that will make it clearer (when tabbing) where you are actually at in the form?  e.g. making the 'Highlight Fields'  option a default at the time of opening the document.

Thanks

Jen