Best hardware configuration for budget multitasking laptop

What hardware configuration should I be looking for in a daily use laptop? My work requires constant multitasking with web based applications; OpenOffice spreadsheet & word processing; reading lots of PDFs; reviewing streaming video, downloaded mp3s & mp4s; joining webinars; plus several miscellaneous installed programs that aren't hugely resource hungry. Because different applications I need are optimized for different browsers, I need to have IE, Chrome & Firefox running, all with multiple tabs always open.

Luckily I don't have to edit images or PDFs, and games are rarely played on this system, but I still often find I'm waiting for the computer to catch up to me. Weight is not an issue, as laptop is used more as a desktop and only relocated once every few weeks or so.

Previous laptop that just died was an HP G62-340US purchased in 12/2010 & upgraded to 8GB RAM. Figured I'd put the money into an upgraded system instead of a repair. Plus, I've been using the laptop screen and one extended monitor, but really want to add a second extended monitor, which I'm told cannot be done on the G62 as it is.

Links to specific models would be hugely helpful, but not as important as understanding which is more important or needs to be balanced between RAM, video memory, processor speed, number of cores, SSD, etc, etc.

Would like to stay around $400 for the laptop, but could stretch to $500 if needed. IF my budget doesn't cover what I need, please advise how much higher I'd need to go.

(Also, local computer store guy really made me think I'm missing out by buying now instead of waiting for a Windows 8 system in the Fall.)

Thanks