If you decide to get rid of AOL you either are going to want to find some 3rd party software to have all of their registry keys removed or you are going to want to format your box. AOL is a bitch, even when you uninstall it, it will NEVER uninstall its own registry keys. Those keys edit some of the base browsing files and more often than not cause complications when you use a different ISP.
As for DSL vs Cable, it depends WHERE you live. If you live in a big city, I suggest you phone up your local cable company and tell them what street you live on, then ask for the users on the node, if you node has 150 or less, its time to sign up, if it has 20 or less (and yes I know of 3 of these in the US) I am moving to your town, and I will be your new neighbour. The reason is that cable is of course a shared internet connection. The majority of the ISPs I deal with set a bandwidth for the node, and a limit for the modem. So you will recieve almost always your max modem speed (usually 1500 kbps) If you have over 150 people on your node, you will notice a great decrease in speed at t=prime times (right after school and around 5-8pm everyday) this is a huge pain in the ass for gaming, and when you are downloading large files. (you can watch tv *any channel* surf, and talk on ANY phone at the same time)
DSL - This is based on how close you are to the local dispatch (phone company), or their closest node & repeater. If you are more than 3-4 blocks from one, dont even bother. But if you are a block or two away, ask your neighbour what thier speed is, yours will be almost identical. Also DSL almost NEVER varies in speed, so if your download is 850 kbps then that is what it always is, no matter the time of day, or how many people are on. The uploads are total crap though (supposed to be set to 128 kbps, so bitch if you are not getting it). The largest downer to DSL comes in the support and compatability. DSL requires line filters, these are crap. They make your tech support experience hell. Other than that, if you are using a cordless phone, or anything else that uses 240khz(kilohertz) - 1.5mhz (megahertz)you can drop your internet connection (which is a MAJOR pain in the ass during a game or a large DL cause your sister/brother/mom/dad/friend wanted to make a call). Please note that while it is possible to be dropped off line due to that, it does not happen everytime, and many subscribers go their entire life (well the time they are subscribed) without experiencing it. The last limitation of DSL is in the cable length. The telephone should not be longer than 8' (as per the ISP) beyond that they will not support the cable, because they can not garuntee the functionality of it. Whereas coax (for cable connections) can be like 28'. Of course either can be supplemented by ethernet cable.
Oh and DSL ranges stated before were downstream only the upstream range is 25khz (kilohertz) - 160khz (kilohertz).
The errors cause from mobile phones generally only occur if you have a 2.2ghz or higher mobile phone in the house though. Due to the strength of the signal they put out.
As for your last vendor, I can not comment because I have no idea who the hell they are. But if you really want I can look into it and give you all the dirty information.