Ad Hoc Recording Studio
For serious high quality recording, here are some suggestions for controlling background noise by recording in a separate room - a cheapo DIY recording studio setup.
A completely silent computer is pretty rare what with fans and hard disks clicking. Some monitors can even have a bit of low hum. For a truly quiet recording environment, the only solution is to put your noisy computer in one room and record in a quieter one with the door closed. ( All that is really needed is a long enough mic cable. But how to control the start/stop, etc? Other programs have a count-in interval which can be used to give yourself a few seconds to walk to the next room before recording starts. This helps but can result in lots of dead air and the hassle walking back and forth when recording numerous takes trying to get that perfect one.
A good solution is to get a long keyboard extension cable and set a keyboard next to the mic. (Finally a use for that old keyboard that came with your previous computer.) Wireless keyboards also work nicely if it's not too far. You can then sit at the mic and use the keyboard shortcuts like R for record, S for stop, ctrl-z to undo the recording, R again to start a new track if you screw up a take, spacebar for playback, etc. A disadvantage is that you have no visual confirmation that recording is taking place, but it is not that hard to train yourself to hit the keys in the right order. If you always hit S before hitting R it is pretty foolproof. (Windows version, other key shortcuts may vary?)
Another useful thing is a pair of headphones in your recording room, also of course requiring a long extension. Using the keyboard shortcuts you can basically sit there indefinitely recording, listening to takes, and recording more without so much as needing to look at your computer.
An actual monitor in the recording room can also be done. (Yet another use for yesteryear's spare computer equipment.) Though monitor extension cords may not be available, it is possible to put a hole in the intervening wall and pass a relatively short monitor cord through back to the noisy computer. With a monitor you will probably want a mouse as well, using either the hole in the wall pass-through trick or (yes) yet another long extension cord.
In a pinch, if the room has a window or a glass door, you can set your recording laptop on the other side of the glass for full visual access. Just don't leave it out in the rain or drop it off the ledge.