The problem I’m having is with the rear derailer (is that the right term?). It doesn’t want to slide all the way over to allow me to get onto the smallest sprocket (of 5), unless I go straight from the third to the fifth, in which case it seems to jump all the way over. The shift lever is one of those that has notches to keep it place, so I don’t really have any control over where it is. Is there something that needs to be tightened or loosened to give the derailer more range of movement?
First of all, derailer is an accepted term. (Personally I prefer the french-inspired derailleur though).
There are normally two screws to set how far the deraileur can travel each way, as well as a cable tension. You could try fiddling with them. In my experience, though, the problem is normally that the entire deraileur (or its fastening) is twisted, and no amount of adjusting will ever get it back to perfect condition.
Have a look at this page (By the excellent Sheldon Brown. What he doesn’t know about bikes isn’t worth knowing.) and see if you want to give it a go.
In your situation, you most likely need to adjust the high-gear limit stop screw. Shift to the highest gear (or as far as it goes), then adjust this screw until the derailleur is aligned with the smallest cog. Then shift to the next gear, and make sure the derailleur is aligned with the second cog. If it isn’t, adjust the adjusting barrel on the shifter cable to align it. The photo at the above link shows a Shimano derailleur; with a SRAM setup, the adjusting barrel is on the other end of the shift cable (i.e. at the shifter).
