Answer to "Rubber foot fell off"Before attempting to glue it back on, you may want to consider simply replacing it with a new one. If you live near an Apple Store, go there and ask if they can replace it. They're often pretty good about fixing stuff like that without charge, or even just giving you a couple of spares if you ask politely. Authorized Repair shops will probably stock them as well but will most likely charge for a replacement. It's worth a shot.
Answer to "Restoring hard drive after replacing - what disk should I use"Given that you want to restore your machine from a Time Machine backup (assuming that your TM volume was backing up the entire boot disk), it may be simpler to just boot from the original disk that came with your machine, run the installer, select the language and then choose the "Restore from backup" item in the "Utilities" menu and follow the instructions to select your Time Machine volume. And remember to repartition the new drive with the GUID layout using the version of Disk Utility contained on the DVD before you restore the volume. Since your MacBook was made before Snow Leopard was released, you should be able to boot and install from the Snow Leopard DVD without any issues, but that will complicate the restore from your Time Machine backup. You may still want to dig out your original disks, though, since the Snow Leopard DVD doesn't contain and won't install the iLife bundle if you're using those apps. The general rule for Mac OS X releases prior to Lion is that a retail DVD will boot and install...
Answer to "Is it possible to replace a Silicone Dome?"If you do use glue to repair the dome, be sure to allow the adhesive to fully cure before reassembling your MBP. Every adhesive I'm familiar with that adheres to silicone will release volatiles during the curing process. Usually this isn't an issue, but in the warm, confined space of the MBP, they could attack other parts. Follow the instructions for your adhesive and double (or even triple) the curing time, just to be sure.