Some windows tilt in after being raised up a little. Then you find the two release tabs on both sides, pull them in toward the middle, and tilt the top of the window toward you. Then, you take the screen out. This is handy if you have two story windows, and you'd rather use an extension poll instead of a ladder. Now there is no reason to climb up there!
Another kind of window that is similar, but worse, are ones that don't tilt in; you have to actually remove the bottom window! Look for two flat metal tabs near the top of the side tracks on both sides. (In some older models, they are actually plastic!) Use your fingernails or a screwdriver to pluck up the bottom of these tabs. These turn into catches for the spring mechanism on both sides of the bottom window. Raise the window until it catches on the raised tabs. Keep pushing up until you see at the bottom of the window that the spring rods are exposed. At this point, you can pull the window to one side (you may have to jerk it hard) and tilt out the side that has come out of its side channel. Then you can pull out the other side, and now you can get the screen out!
When taking out this kind of window, make sure you pay attention to any alarm magnets. You can knock off the magnet if you pull the magnet side into the channel first. A similar problem arises when you have windows that slide sideways in their top and bottom channels. These windows will come out when you slide them over half way and lift them out of the bottom channel. If the alarm company employees aren't thinking about this, they will put the magnets on the top and make removing the window impossible. Impossible, except that I just knock the magnet off and glue it back on later. This is necessary if you want to clean those special windows the idiot window companies gave us that have screens that will not come off from the outside.
I use Lime Away, The Works, or toilet bowl cleaner. These will get out some stains, but some will come off with nothing I have ever found. Redirect those sprinklers NOW.
I believe that insulated glass, in its present form, is a fundamentally flawed idea. For those who don't know it, an insulated window is made of two pieces of glass with an air space separating them. This dead air space, filled with inert nitrogen gas, is supposed to reduce outside noise and lower temperature loss through the widow. It does do an excellent job of noise reduction, but it does a negligible job of saving energy.
The dead air space is protected by a rubber, silicon or petroleum based seal that keeps the totally dry, dead air in and the moist air out; for a while. The basic problem with this concept is that these windows get alternately hot and cold 365 times a year, especially if the windows get a lot of sun exposure. That means the seals expand and contract until the inevitable breach occurs. It may take 15 years, or 15 days, but it's coming. When it does, the air inside the window will expand and escape out the breach in the seal.
When the window cools, the air inside contracts and sucks in the highly humid air we have here in Florida. Thus begins the fogging effect that we begin to notice as that air gets hot and the moisture turns to steam in between the panes. It usually starts as just a small amount, but it grows and grows until the window is actually dripping wet inside when it cools. I have seen this happen for 20 years, even to windows that have never been power washed.
Window Man is my choice. He has all the parts, and even makes screens. He's also very reasonable and he's been in business for at least 20 years, Call him at 375-6575, or go to his shop at 206 NW 10th Ave., behind the old Main St. Publix (which is next to the new one).