Shareaza

2.5.3.0 constantly logs this error at the rate of 3 per second:

Skin load error: Failed to load watermark. Element: LargeLogo. File: 00400000$196

Also the [+] symbols in front of expandable list items are corrupted and there is lots of other corruption going on when moving selection in the lists.
I have tried all skins although usually using no skin at all - graphics corruption exists with any skin or w/o skin at all.

I'd try a reinstall first after downloading a new copy of the installer, since that sounds like file corruption. It could also be some sort of a file access rights problem.