Looking to make an upgrade for SWTOR

So I have been playing SWTOR for a bit now and I have been experiencing a few issues and I have a feeling I'm about due for a few upgrades. The main issues I have been incurring are long loading screens (compared to my g/f friends new laptop my loading screens take for ever). The other issue I have is when I try to log out and quit SWTOR the game locks and takes on average 10minutes to close. I have no idea what the cause for these problems is but I have a feeling it will require me to make some upgrades.

Here are my specs:

ASUS P5K-E/WIFI-AP LGA 775 Intel P35 ATX Intel Motherboard
http://www.newegg.com/Product/Prod [...] 6813131196

Intel Core 2 Quad Q6600 Kentsfield 2.4GHz LGA 775 Quad-Core Processor BX80562Q6600
http://www.newegg.com/Product/Prod [...] 6819115017

Seagate Barracuda 7200.10 ST3500630AS 500GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Hard Drive (Perpendicular Recording) -Bare Drive
http://www.newegg.com/Product/Prod [...] 6822148136

COOLER MASTER eXtreme Power RP-550-PCAR 550W ATX from factor 12V V2.01 Power Supply
http://www.newegg.com/Product/Prod [...] 6817171016

I currently have 2 of these for a total of 4GB of memory
CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model TWIN2X2048-6400
http://www.newegg.com/Product/Prod [...] 6820145590

I have will probably upgrade to Windows 7 soon
Microsoft Windows Vista 64-Bit Home Premium for System Builders Single Pack DVD - OEM
http://www.newegg.com/Product/Prod [...] 6832116204

Radeon HD 6770 PCI Express 2.1 1 GB GDDR5