Generally, a pass peaking over 30 degrees is considered a "good" pass.
However, many good contacts are possible from 5 to 30 degrees elevation from W8SH.

AO-51: Schedule
VO-52: Full-time linear transponder
SO-50: Full-time, must be activated with 74.4Hz procedure as noted below.
AO-7: Frequently operational in UHF/VHF mode, during SUN EXPOSURE ONLY due to failed batteries.
ARISS: Usually in packet mode, at times scheduled voice operations are noted at RAC

Detailed Satellite Status & Frequencies:

AMSAT Satellite Status

Operations:

FM Operation Tips
SSB Operation Tips

AO-51 [FM] and VO-52 [SSB] are generally the easiest and most reliable satellites to work.

AO-51: FM
Downlink power: Normal-400mW | High-1300mW [per AO-51 control operator group]
Uplink power: 5W ERP is plenty, but QRM sometimes requires full power to overcome
Strong downlink signal
Hang time: Keyed continuously during pass
Uplink: 145.920MHz FM
Downlink: 435.300MHz FM
Digital Uplink: 145.860MHz 9600 baud
Digital Downlink: 435.150MHz 9600 baud
BBS Call: PECHO-12
B'cast Call: PECHO-11
Hear Contact

VO-52: SSB/CW
Downlink power: 1000mW maximum--shared across passband--Moderately strong downlink
Uplink power: Suggest 20W ERP (at W8SH, set TS-2000 to Power: 10)
Uplink passband: 435.220 to 435.280 MHz LSB
Downlink passband: 145.870 to 145.930 USB
Beacons: 145.860 (Telemetry) | 145.936 (Unmodulated)

SO-50: requires 74.4Hz PL for 2 seconds.
This starts 10 minute fixed timer--must be reset every 10 minutes.
Then, switch to 67.0Hz PL on uplink to open squelch.
Downlink power: 250mW--but spinning of satellite leads to fades and changes in circularity.
Uplink power: 5W ERP is plenty, but intentional QRM sometimes requires full power to overcome
Hang time: 1/2 second
Uplink: 145.850MHz
Downlink: 436.795MHz

AO-7: SSB/CW
Downlink power: Unstable and varying--FMing due to poor to no regulation of DC bus
UHF/VHF mode:
Uplink power: Suggest 40W ERP (at W8SH, set TS-2000 to Power: 20)
Uplink-432.125 to 432.175 LSB | Downlink-145.975 to 145.925 USB
Beacon: 145.9775MHz
VHF/HF mode:
Uplink-145.850 to 145.950 USB | Downlink-29.400 to 29.500 USB
Beacon: 29.502MHz
Note: The beacons are often several kHz off frequency (presumably, along with the passband)

ARISS: no PL required
Downlink power: 10W--Strong downlink
Uplink power: 5W ERP is plenty, but high usage sometimes requires full power to overcome
Packet bursts are heard about every 15 seconds when packet mode is active.
Packet Uplink: 145.990MHz
Voice/crossband repeat/Packet Downlink: 145.800MHz
Voice Uplink (for rare occasions when astronauts are on voice): 144.490MHz
Crossband Repeater Uplink (rarely active): 437.800MHz
Digipeater callsign (for "UNPROTO CQ VIA..."): ARISS
BBS Callsign: RS0ISS-11

Hear ISS Astronaut making contact with school on 16 Nov 2005

ARISS Packet Parameters:
1200 baud AX.25 | UNPROTO CQ VIA ARISS | Auto LF OFF | Packet Length: 72 | MCOM ON | MCON ON
Kenwood TS-2000 UNDOCUMENTED COMMANDS: PASSALL ON | SOFTDCD ON

Just type away when you hear packets--remember that the squelch must be closed between packets to allow the TS-2000 to transmit. Use the TS-2000 in standard-non-satellite mode with Split TX frequency (this allows you to monitor other frequencies on the SUB receiver, if so desired).
Frequently, ARISS operates as a digipeater--you will see people calling and chatting much like on RTTY or PSK31. You will notice that you see your own typing echoed back to you through ARISS.
However, the TS-2000's built-in TNC doesn't always decode well-even on strong (S9+) signals. This can be very frustrating.
Do NOT try to connect to other stations directly through ARISS.

Check out the Kenwood TS-2000 page for more hints and tips
Kenwood TS-2000 Internal TNC

Nova Doppler shift: It is important to remember that the satellites due to age, temperature, etc. can be a few kHz off from where Nova and other software predicts. As most FM VHF Doppler shift is less than 3kHz, it is usually benefical to NOT move VHF TX off of satellite center freq.
Also, the computer tuning cannot account for the satellite itself being off frequency--the operator must compensate for this