We have a ticking noise from the master shower (noise comes from the wall) when I turn on and it continues until I shut it off. What causes this? Any suggestions on what's going on? Is this a major plumbing issue?

I've also recently been noticing when I turn on the cold water that it comes out brown for a little while. I know its rust, but what's it coming from? Is there a simple solution to try first?

Lastly, I've noticed when I walk down stairs on our travertine floor that one particular area is "warm". Its close to the downstairs closet. Could this be a line break? If so, does the closet have any significance? Is this a major issue?

I'm not a very handy person and have no idea how my water works in the home.
Please help!

Items 2 & 3 suggest a break. There is a possible underground water line.

Make sure all the water is off in the house. Go take a water meter reading. Wait a few hours and then take another. No water should be consumed.

Ticking noise could be junk in the line if there is a break, otherwise a possible bad faucet seal.

Has your hot water heater been drained of sedament?

OK. Checking the water is a good idea. I drained the water heater about 4 months ago... I left it running for about 30 minutes.

We have a ticking noise from the master shower (noise comes from the wall) when I turn on and it continues until I shut it off. What causes this? Any suggestions on what's going on? Is this a major plumbing issue?
Knocking, popping, creaking and crackling pipes are a common complaint, especially in colder weather. I can tell you what's happening and take the mystery out of it but you're not going to like the repair. When a draw is made on a hot water line the line expands against a pipe strap next to a stud and when you drain hot water from your tub or shower it goes into a chase that is a little cooler then room temperature. The heat expands the pipe causing it to rub against the stud to which it is pipe strapped. This is the sound you hear. As it cools it contracts and the noise is heard again. To repair it you must tear open the walls and locate the pipe strap that's causing the problem and shim it tight. Most people when they learn what causes it just elect to live with it.

I've also recently been noticing when I turn on the cold water that it comes out brown for a little while. I know its rust, but what's it coming from? Is there a simple solution to try first?
Do you have a older home with galvanized pipes? Are you on a pump or city water? If on city water Has the water department done any work on the main lately? As a rule it's mineral buildup from the water heater that puts rust in the hot water lines. In your case tryflushing out the cold lines.

I've noticed when I walk down stairs on our travertine floor that one particular area is "warm". Its close to the downstairs closet. Could this be a line break? If so, does the closet have any significance? Is this a major issue?
This complaint concerns me the most. A "hot spot" in the slab indicates a broken hot water line under the slab. And yes, this is a very major issue. Shut down all water usage in the house and go out to the water meter. If the little pointer's moving that tells you that there's a leak in the water system. This hits you with a double whammy. You're paying for the water plus the expense of heating it.
Since water will see the path of least resistance the leak could be some feet away from the warm spot we usually call in a locating company such as Sleuth. They will pinpoint the leak, break up the cement, dig down to the lleak, bag the dirt and bare the pipe. The plumber can then come in, drain the system down, repair the leak and patch the slab. Good luck, Tom