New
#11
Probably---if for no other reason than that it would remove your 4 GB RAM limitation.
You can't go above 4 GB on your current motherboard even if you converted to 64 bit.
Nearly any new machine would support 64 bit and much more RAM.
Windows 7 Home Premium has a 16 GB RAM limitation, but that may well be plenty for you.
If you buy a new machine with Windows already installed, pretty good chance it will be 64 bit Windows.