Need help choosing a smart phone for internet use

I finally got to investigate a wireless news ticker and the sidekick 2 by t mobile. It seems it does not process java script too well or cookied websites. I was told by the guy at the t mobile stand that I can get any smart phone and swap out the sim card from a phone they sell and he would buy the phone back from me and I can surf the net and make calls depending on the plan I choosed. He said before tax I was looking at 30 bucks a month for unlimited web and 30 or 300 minutes of talk time.

So, what I am trying to do is find a smart phone that will browse any website, not necessarly format it to fit the screen. I am leaning towards to a microsoft phone for the web browsing, but kind of like the palm. Of course last time I tried my palm pilot online with a palm modem, many websites I could not visit like yahoo mail because of cookies or java script with the free web browsers I tried. Tha tkind of leads me to the microsoft power phones.

Do any of you guys have any advice on this? Anyone have a used one they want to sell? I do not care if it is beat up, as long as it works and the screen is viewable inside or out. I do not care if it is color or monochrome.

Thanks

I've had a Sprint Treo 650 since January and have been very happy with it. I haven't run across a web site yet that it's Blazer browser couldn't display in some fashion. However, sometimes I have to do a lot of left/right/up/down scrolling to see everything. I pay an extra $15 per month for unlimited data access. With it's USB sync cable to my laptop, I can also use it as a wireless modem.

Since I used to carry a Palm m505 and a phone, this was a good option for me.