I took the bike out to test the gears last night, five minutes turned into a half hour. I don't think these are considered friction shifters, as everything says SIS on it and the levers click into place, at least for the rear gears. My first impression is that all the rear gears are in good shape and don't need replacing except the granny gear, which is noisy and doesn't seem big enough to help me get up hills. The noise almost sounds like the chain is hitting the spokes but considering there's a chainguard in place and I got off the bike to test and saw it wasn't hitting when turning tells me the noise must just be the somewhat crooked teeth banging around on the chain.

I'm going to the LBS and getting a new chain and inquiring about a new rear cassette. Shifters seem good enough to keep as do the brakes.