You have to provide a little bit more info. Do you know what version of WM5 you have installed? The latest one is A12. If you don't have it, download it from Dell here:
Drivers and Downloads. Follow directions given.
After flashing A12, look at my post
here on WM6.1 ROMS. Keep in mind that these are 3rd-party ROMs that MAY have bugs and flash at your own risk! It voids your warranty if you flash. Then, tell us and we can help you flash step-by-step.
Personally, I recommend LennySh's L11 WM6.1 ROM because of it's extreme speed.