Well, for simple (or complex) file browsing on my home PC via WiFi on my HTC Desire, I use "EStrong
" file manager
xda-developers - View Single Post - Best file manager (no, it is not ASTRO)
It works. I could copy, cut, paste from home PC to HTC Desire and vice versa.
It has FTP client as well!
Note: If you have issue with HTC Photo Album does not recognize images that you copied from home PC using file explorer or FTP, use "SDRescan" app to re-scan your sd-card.