I found the lab a little frustrating at first. You just show up there and don't know how to get him to DO anything. In essence there are three "stations" in this room. First, the microscope. You can drag hairs over here to look at them, or to compare two hairs to each other.

Next, the computer. Use this to look up fingerprints, to compare fingerprints to a rap sheet you have, or to do other research on schedules or people.

Finally, there is Greg. You hand him blood to do testing. Note you can NOT ask him to compare samples. He will do it by himself when he feels it is appropriate. So you have to keep going around looking for more blood and when he has enough of them he'll do his comparison. He'll also investigate other items you hand to him.

Right now you only have one hair and a few prints. Use the computer for the print analysis. The TV remote matches the manager's fingerprints. You get his rap sheet - he has been arrested for assault. Suspicious. There's no match for the TV set. Note that you can compare the TV set fingerprints against the manager's rap sheet if you want. They don't match.

Give the blood to Greg for him to analyze - now he needs more to compare it with.

Time to head to the autopsy room!

CSI Crime scene Investigation Walkthrough