98 Cherokee Classic Issues

1) Infrequent difficulty starting and staying running. 2) What is that wire or tube looking thing hanging down next to the rear right tire. 3) How do I change brakes? 4) Voltage irregular at power source when restarting vehicle. Basic Questions for seasoned owners probably. I think it is a well kept 98, from Michigan w/ previous owner until I bought it a couple months ago and brought it home to Va. Fog lights don't work anymore nor the Skymate sunroof, both not needed really to work and the sunroof doesn''t leak so who cares. 170k miles. I will be driving this daily (7 days a week), at least 60 to 150 miles each outing, with no forseeable time to drop it off and get it worked on, I can't afford it anyway right now anyway. I know how to change a tire or plug it with a plug kit, that is the extreme of my working knowledge of breaking a sweat working on a car. 1) Sometimes when first starting after a several hours of sitting, she doesn't turn over and start without goosing the gas a touch. If she turns and starts without touching the gas like she should i got no problem, but if I tap that gas then more than likely she will stall once started. I have to keep one on the gas at all times after that until I am out of the drive on the road and going for about a mile. I'll test her out by letting my foot all the way of fthe gas, the battery gauge will dip down, the lights will dim and then she'll kick in (so far) and be fine. No more issues with the power after that excercise. Once the battery light stayed on for an entire 40 mile commute, but only once. Every other time she's been fine or the above hand holding will get me to the point where she behaves. This problem may be tied to issue 4. 4) I have a GPS sometimes for work powered up by the dedicated power source only when the vehicle is active or during the few hours when I am making deliveries so allot of starting, stopping, turning off and on etc etc., At first when I first bought her the power was constant and the GPS didn't blink off when I started up. Now when I turn her off the GPS stays on, only when i get back in and restart the jeep does it turn off but it isn't supposed to. 2) Tube or wire, dangling from or close to mid tire height rear right tire. I've seen this thing hanging down since I bought it, and seen it also on what looked like the same year jeep as mine on the road. When I go off road (nothing to serious) to find a good fishing hole I don't want to mess this thing up if it is supposed to be there but it seems to me it could snag on something, lord forbid it may be the brake line or something!? 3) I am not mechanically inclined, I own some tools, but if directions (yes I read) are not painfully crystal clear you can bet your last dollar I will get it wrong. Is the haynes book or Chilton the thing to get? I need to get savy enough I can maintenance this baby myself, and I am as ignorant as a newborn and as shortempered as they come. Obviously the easy thing to do would be to take it to the shop, but I can't afford it and like the idea of being able to take care of at least the basics myself. Does anyone have some written instructions or can write some up (Richard J. Pierson, your oil change instructions were great, got anymore)? A link? Any thoughts or suggestions on the above or general care etc etc would be greatly appreciated.