Okay dude.... you ARE being a bit rash and ignorant, and most of the time I only respond to posts like this with sarcasm and advice on dropping the phone all together because you've already got a mindset that it sucks, and there's nothing to be done.
You've got way too many problems here. Do a hard reset, make it factory default. DO NOT INSTALL A TASK KILLER. THE PHONE IS NOT A WINDOWS COMPUTER. IT OPERATES DIFFERENTLY. Get that? Your phone will run only what it can handle. If you kill the tasks that are running, the phone is then confused and forced to re-do everything it had to do to open the application(s). If you DON'T kill the processes, the phone tosses the programs to the side in a standby mode, NOT USING CPU.
In a basic, BASIC, sense (so you can't possibly say anything back to it), what I'm saying is that you should just shut up and let your phone do it's thing. Realize this, our phone is NOT the most recent, there WILL be lag, and sluggishness. If you want the newest, fastest thing, wait till the 4th of June and get the EVO.
Do a hard reset, and completely leave out a task killer, do not, do not, DO NOT, install one. Let your phone do it's thing, and just sit back. If you really don't like your phone, just drop it and get a Nextel i850. Trust me, it's much simpler. You can't possibly mess that one up.