can't get online

I have a DSL connection.
The other day the desktop (Windows 7, wired connection to router) started acting funny. My internet stopped working and I called the phone company. THey told me to see if the AUTOMATICALLY DETECT SETTINGS button was selected under internet options. It was, I unchecked and all was okay again.

THe next day, I was having trouble getting ports open. At canyouseeme.org, I was getting hit and miss. I have a Netgear router, static IP address, and certain ports forwarded. While trying to get those ports working consistently, I started having problems with the actual internet connection.
Later in the evening, the PC started acting strange, and then for several hours, I couldn't even get it restarted.
Finally, something gave and I got it restarted.

Now the internet is reading connected and online, but I am not connected.
The laptop is working fine via the wireless router. Sometimes, the internet icon has the yellow exclamation point (no access), and sometimes it doesn't (internet access).

I tried three of my network adapters and even bought a new one and new cable today. No difference.

Ideas?

Thanks .

You mentioned that the operating system was causing problems, maybe the problems are related? If I remember correctly I had the same problem with my Vista Ultimate pc. After, reinstalling Vista in seemed to solve the problem.

To trouble shoot network connectivity, always start with the simple thing first. You mentioned that your computer is assigned with a fixed IP address, so I'd put it back on DHCP and see if it can get an IP addr from your router. Open command prompt and do an "ipconfig /all". Note the result. Do you have a valid IP address? Do you have a valid gateway?... Next, try to ping itself (127.0.0.1) and then ping the router and then ping some host outside of your network such as google.com... If you can get a ping reply from all the pings mentioned above then you Internet connection is OK. You then focus on the browser settings if you still can't get to the Internet with your browser. Try to reset it to default settings.Make sure you don't use any proxy in connection setting...
Hope this helps.

Thanks both.
Stanav, I called the phone company again and we basically went through the steps you mentioned. They were stumped for a while, but eventually it started working. Of course it started working in a configuration we'd already tried. Anyway it's on for now until next time.

The orginal problem I had is still there. I can't get ports open reliably.
At canyouseeme.org it alternates between "connection was refused" and "connection timed out" with an occasional short-lived "success, your port is not blocked".
I currently have the firewall turned off, McAfee turned off, and the ports I want open in the router.
I've confirmed the IP address v4 192.168.1.5 (first time I've had a five, but it's connected, so...)
so the port forwarding is correct, uPNP is on. I don't know why the ports are not open.