After more than 15 years experience with PC technology, there are a few constants. Following is what I would check out if I were looking at a client's PC ...Also, the following are in conjunction with each other, in other words, the more you can effect suggested changes the quicker your appl's will start.
1) Defrag your disk
2) There are different things to check depending on whether you have NTFS, FAT, or a FAT32 file file system, I will leave that alone until there is more info.
3) Check the size/space your ID is using, on XP, select My Computer - Properties - Advanced - User Profile/Settings...see what the size of your Profiles are, the larger they are the slower your appl's will start. If your ID is in the mid-MB to GB level, in terms of space, create another ID and see what a difference it makes. The reason it can make a difference is that typically over time a user will add appl's, upon, appl's etc. until it takes awhile to look through the registry and the disk to find what you have requested, the less you have the quicker the appl will be found.
4) Make sure your disk is not "thrashing" by that I mean swapping out to disk, the disk is the slowest part of your system, therefore try not to run more appl's than you need. If you do, (and don't have sufficient memory) disk swapping will be a problem.
5) One sure way to deal with all of these things I have mentioned is to save your data, then wipe your disk and re-install. After all, the suggestions I have made do virtually the same thing w/o re-installing.
6) Sorry there is no magic in getting the speed back, be careful of the tools out there, some of the registry pgm's will delete so much, you won't be able to start your PC. Always backup your data, remember to backup your "system state" with "Restore" or other similar utility. Good luck... I can not assume any responsibility for the outcome of your PC, that my friend is all your's.
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