1. Yes if they have deteriorated or hardened beyond being able to be adjusted to perform their sealing function.
1a. Yes, but be aware that the traps for the novice probably equate to those in overhauling your own car engine, or a gear box. Technicians work for years on saxes before they begin to think they really know what they are doing. That is because they tend to be AWARE of how much they don't know. You will probably save a lot of money and time if you find out how much you don't know. Money spent on the following would be money saved: THE COMPLETE WOODWIND REPAIR MANUAL - by Reg Thorpe, available from
http://www.napbirt.org/
2. "Are these pads very good quality/ produce good sound? (Im going to be in 11 th grade/ junior in high school)" Yes, as has already been said. The better the pads, the more skill is needed to get them sealing.
a. "i wont encounter any problems while using them will i?"
There is hardly any job done on a woodwind that does have a myriad of problems lurking around it. Without experience, you may create problems as fast or faster than you solve them. Buy the book!
3. "Ive read lots of instructions on installing pads, so can anyone reiterate the basic procedure of pad replacement?"
The basic method is to glue them in with a temperature sensitive glue. There are many variations on this theme. YOu say you are already aware of at least a few. Each has its own advantages and difficulties. You choose! To disuss all the variations fully would take a lot of writing.
Variations have been written many times in this forum. Do a search, or Buy the book.
For every method of successful pad installation and adjustment,the devil is in the detail. If instructions are not quite a few pages long, then be aware that they really are superficial. As an indication of the detail, the following is nothing more than a SUGGESTED ORDER of adjusting a sax, based on a quite specific method of installation, without even going into the how of the adjustment.
Post 4 at
http://www.saxontheweb.net/vbulletin/showthread.php?p=507033#post507033
Putting pads in is a very small part of getting a re padded sax working. It's a big job.
Use shellac sticks for adhesive. It's the easiest for a novice to use.