I know that there are ET clients that people have made for windows 7 , but theyre made by other clan leaders/programmers and often have other clan stuff in them. But all of that is propably cleanable , and u can still play in ETc| in those clients , and with normal ping. My laptop is running windows 7 too and i oftenly cant get in ETc| SexCup in there or i have huge ping there.
At home my pc runs windows xp sp3 and works great. but my client is bout 6 years old i have never upgraded it and it has a long history, so i dont know howmany mods n stuff i have here
I also know that people have difficulties installing ET nowadays into PCs since most of the servers wont work , i know that the punkpuster needs upgrading and some other stuffs.
I hope this post was useful but in the meanwhile try running the windows 7 in safe mode by pressing F8 or F6 while u have powerd on the pc and run the ET in windows xp compatibility mode + low resolution at 1st like 840x640. If that doesnt work and u really wunt to play ET , u have to think bout downgrading windows 7 to windows XP or Linux. Some Ubuntu-s play ET also , but they mostly are rund on CD-s.