I bet "the twerp" was probably restricted by a rule where they can't recommend Android apps. It's probably a liability issue. If you called and said that Travis at US Cellular told you to put SomeShadyApp on your phone, and now something's gone wrong, I imagine Travis (some random name) would be in a whole heap of trouble.
Some of the ROMs will make it so the power/sleep button hangs up a call. I think this is a stupid feature, since I'm in the habit of sleeping my phone in a call, since I use a Bluetooth earpiece. I don't want my pocket swiping the end call or speakerphone sliders. It's never happened, but my pocket has made calls, so you never know.
Rooting your phone is like giving yourself a key to your house. Technically, somebody could take it from you and steal your stuff. But it probably won't happen if you're smart. If you go installing random apps, yeah, maybe one of them will do bad things. It could happen. But we're talking about the Samsung Acclaim, a phone with 160MB of RAM. Taking out the redundant US Cellular apps (My Contacts Backup -- WTF is this? Gmail does this automatically; Your Navigator Deluxe -- WTH? Every Android phone comes with Google Maps, the best GPS/map/navigation smartphone app bar none; Tone Room Deluxe -- don't we pay enough for smartphone service? Besides, Ringdroid will make ringtones for free) will do far more for your phone than the latent risk of a bad app stealing your info will hurt it. Not that I recommend rooting for everybody, but if you can make your phone usable, I'm all for it.