Should I get a rectangular or mummy sleeping bag?
To make this decision easy, consider one thing:  How important is weight?  All things being equal, mummy bags will weigh less (because they are smaller and need a little less insulation due
to better efficiency) and pack down smaller.  The downside is that they are not as roomy.  All the bags in our household are mummy bags.  The somewhat constricting shape does take a little getting used to, but once you are used to them, they are quite comfortable.  REI carries a fantastic selection of bags including their own brand which is very good.

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Answer 2:

Which is better, a propane or gas stove?
That all depends on what you will be doing.  If you are going backpacking into the mountains, then a lightweight, white gas stove is your best choice.  If you will be predominantly car camping, then I recommend propane.  My preference is to use propane whenever I can.  It's cheaper than gas, no pouring is necessary, no pumping or priming is necessary, and, generally, propane stoves have a higher BTU output rating.  You can even buy propane stoves with ignitors so you don't have to light them with a match.

Question 1:

Answer 1: