First, check to see if there's anything that's obviously gobbling up all your RAM. Press Shift+Esc to bring up the Chrome task manager, and sort by memory usage, then by CPU utilization. You'll probably see just a couple processes that ran away with all your system resources. You can try to kill the hogs to speed things up again. Also, try uninstalling Flash or get something like FlashBlock, which prevents Flash applets from running unless you click on them to activate them.
The SSD will only help if you put your Windows page file on it. It's probably not the best use of an SSD, since paging (i.e., lots of writes) will shorten the life of the drive, but in real-world terms, the drive may last long enough to last until you get a new computer. If you store files on the drive in addition to using it as a paging volume, the wear-leveling algorithms won't be as effective, so I'd just recommend using drive exclusively for paging and caching.
If you think it's primarily a hardware limitation, you're probably better off upgrading to 6 or 8 GB of RAM, assuming you're running a 64-bit OS and your motherboard has free RAM slots and/or supports higher-capacity modules.