With my kindergarten classes, we always worked on the ABCs section until they were proficient in their letters and sounds, then we moved on to Learn to Read. Both of these sections are complete free. The ABCs page works on letter naming, letter sounds, and both uppercase and lowercase identification. Learn to Read provides sight word practice, phoneme blending, and word family games.
I had E first try out Starfall when we got our home theater PC. She was 2 1/2 years old. Lately, we checked it out again and I stumbled upon new (to us) sections (that actually published about a year ago) called More Starfall.
...and sorting by several attributes.
Starfall offers one month trials to anyone who requests them. When ours expires, we'll definitely be subscribing. To get your free trial, just email Starfall and ask (and let them know that Still Playing School sent you, please)!
In addition, their homeschool kits are very tempting! If I didn't already have tons of supplies, I'd definitely be starting with one of these!