"Ten seconds for a cached start is still slower than an uncached start of 2 seconds... just saying."
-what lies? 10 sec uncached! not cached...and you'll be closer to the truth, but if thats not enough, 10sec for good stuff, vs 2sec for rubbish(can inc. that junk called chrome in this side aswel).. and thats just startup speed, what about your actual browsing session and delays incurred through the a crap ui, page rendering, control, lack of decent enhancements etc.. you choose.. oh..you chose fail!
anyway its probably best you don't debate on taste, you're defending IE against Firefox (which is albeit carried by its extensions and addons) ...but its still a no win situation for you 
"I've been using Firefox but there are a couple of things that bug me. One thats getting on my nerves is that often when you close Firefox, it really doesn't shut down. Then if you try to run it again, even sometimes even after a minute, you get a stupid message box saying 'Firefox is already running'."
Well you didn't say what version, did you even do a search for "Firefox is already running"? , and if you're closing FF and wanting to open up again straight after like after installing/testing an addon/theme etc, then you're doing it wrong..because that is where you use restart instead.
Anyway I've got plenty of annoyances to do with FF and its inabilities including some of its addons, its far from perfect, but right now its better than the rest have to offer when you add it all up.