Replacing Factory Muffler

So, my 15-year old factory muffler finally rusted through as I saw my tailpipe flopping down the interstate in the rear-view mirror a few weeks back (surprisingly, the tailpipe is in great shape, even after the tumble). The baffle-material blew out and she got LOUD [which some of my friends would call a good thing, but I hate waking up the neighbors when I move the truck at 6am)... so its time for me to put a new muffler on my '96 4x4 Taco...

I've never done a muffler job before, but it seems fairly straightforward... Looking under the truck, I see the tailpipe (or where it should go) connecting to the muffler (outlet to tailpipe is disintegrated), and then a pipe from the muffler to the (not sure of proper term) exhaust manifold (?)... so I have a few questions.

#1) Doing a quick search online, I see all sorts of shapes and styles of mufflers that supposedly fit my Taco... is it easiest to replace with a muffler identical to the factory, or will any of these $30 deals work (all I really care about is the truck being as quiet or quieter than it was previously), or does installing a cheap cherrybomb-type require extra work connecting everything up? Or, what are the cons of installing the cheapest muffler I can find ($20-$30) verses the one identical to factory ($50)... I'll gladly pay the extra $30 unless it really doesn't make a difference in noise or performance...

#2) The connecton of pipes that run from exhaust manifold (?) to the muffler intake seems to be fused together at the connecting point (one slides into the other)... either intentionally or by rust (or intentionally and THEN by rust). Just wanted to verify if indeed there is some type of sealant holding them together or if its just rust, and what is best to loosen them up to separate the two?

#3) Anything else I need to know before doing my first muffler job?

Thanks for your time in advance, and apologies for my long-windedness.

[ETA for clarity]

 

Thanks for the info! I knew I didn't need a manifold, I just didn't know what to call the thing near the front that has a pipe coming out of itself and the pipe ends at the muffler intake... (didn't know if that was the manifold or something else). As for the muffler, I'll stick with the factory style and pay the $50... as for the pipes, yep the only way they can be held together is welded (I thought, perhaps naively, they might just slide together and the other components prevent them from coming apart)... so given they are welded, I can just saw off past the joint and use another piece of pipe to connect up to the new muffler, measuring with caliper as you suggest...

 

So, it occured to me today... if my current muffler is welded onto the pipe, how do I attach the new fitting for the new muffler without welding it on?